Why is my availableTimes list empty in Firestore when saving PlaceData in Android?

I'm trying to save user-selected times to Firestore as part of my PlaceData object, but although the log shows the data is being sent, the availableTimes array in Firestore remains empty, while other fields are saved correctly.

I defined my data class as follows:

KOTLINCopied
data class PlaceData(
        val name: String = "",
        val capacity: Int = 0,
        val id: String = "",
        val placeImageUrl: String = "",
        val availableTimes: List<String> = emptyList() // Firestore can handle this
    ):Serializable

I implemented the repository function like this:

KOTLINCopied
override suspend fun addPlace(placeData: PlaceData): Flow<RootResult<Boolean>> = flow {
        emit(RootResult.Loading)
        try {
            val currentUser = firebaseAuth.currentUser
            val userId = currentUser?.uid
            if (userId != null) {
                val placeId = firestore.collection("users").document(userId).collection("places")
                    .document().id

                // Create a map of the data to save
                val placeInfo = mapOf(
                    "name" to placeData.name,
                    "capacity" to placeData.capacity,
                    "id" to placeId,
                    "placeImageUrl" to placeData.placeImageUrl,
                    "availableTimes" to placeData.availableTimes // Ensure this is a List<String>
                )

                Log.d("FirestoreSave", "Saving place: $placeInfo")

                // Save the data to Firestore
                firestore.collection("users").document(userId).collection("places")
                    .document(placeId).set(placeInfo, SetOptions.merge())
                    .addOnSuccessListener {
                        Log.d("FirestoreSave", "Place saved successfully!")
                    }
                    .addOnFailureListener { e ->
                        Log.e("FirestoreSave", "Failed to save place: ", e)
                    }

                emit(RootResult.Success(true))
            } else {
                emit(RootResult.Error("User ID is null"))
            }
        } catch (e: Exception) {
            emit(RootResult.Error(e.message ?: "Something went wrong"))
        }
    }.flowOn(Dispatchers.IO)

Below is the Composable UI that collects user input and uses a mutable list for availableTimes:

KOTLINCopied
@Composable
fun AddPlaceDialog(
    onDismiss: () -> Unit,
    onSave: (PlaceData) -> Unit,
    onImagePick: () -> Unit,
    selectedImageUri: Uri?,
    context: Context
) {
    var expanded by remember { mutableStateOf(false) }
    var customPlaceName by remember { mutableStateOf("") }
    val availableTimes = remember { mutableStateListOf<String>() }
    val timePickerDialog = remember { mutableStateOf(false) }

    AlertDialog(
        containerColor = Color.Black,
        onDismissRequest = onDismiss,
        title = {
            Text(
                text = "Add Place",
                style = TextStyle(color = Color.White, fontSize = 25.sp)
            )
        },
        text = {
            Column(modifier = Modifier.fillMaxWidth().padding(16.dp)) {
                // Image Picker
                Box(
                    modifier = Modifier.fillMaxWidth()
                        .height(128.dp)
                        .clip(RoundedCornerShape(8.dp))
                        .background(Color.White)
                        .clickable { onImagePick() }
                        .align(Alignment.CenterHorizontally)
                        .border(1.dp, Color.Black, RoundedCornerShape(8.dp))
                ) {
                    selectedImageUri?.let { uri ->
                        Image(
                            painter = rememberAsyncImagePainter(uri),
                            contentDescription = "Selected Image",
                            modifier = Modifier.fillMaxSize(),
                            contentScale = ContentScale.Crop,
                        )
                    } ?: run {
                        Icon(
                            imageVector = Icons.Filled.Add,
                            contentDescription = "Select Image",
                            modifier = Modifier.align(Alignment.Center).size(50.dp),
                            tint = Color.Red
                        )
                    }
                }

                Spacer(modifier = Modifier.height(16.dp))

                // Place Name Input
                TextField(
                    colors = TextFieldDefaults.colors(
                        unfocusedContainerColor = Color.White,
                        focusedContainerColor = Color.White,
                        focusedTextColor = Color.Black,
                        focusedIndicatorColor = Color.Black,
                        unfocusedIndicatorColor = Color.Black,
                        unfocusedLabelColor = Color.Black,
                        focusedLabelColor = Color.Black,
                        cursorColor = Color.Black,
                        unfocusedTextColor = Color.Black
                    ),
                    value = customPlaceName,
                    onValueChange = { customPlaceName = it },
                    label = { Text("Enter Place Name", fontSize = 13.sp, color = Color.Black) },
                    modifier = Modifier.fillMaxWidth()
                )

                Spacer(modifier = Modifier.height(16.dp))

                // Add Time Button
                Button(
                    onClick = { timePickerDialog.value = true },
                    colors = ButtonDefaults.buttonColors(containerColor = Color.White),
                    modifier = Modifier.fillMaxWidth()
                ) {
                    Icon(imageVector = Icons.Filled.Add, contentDescription = "Add Time", tint = Color.Black)
                    Spacer(modifier = Modifier.width(8.dp))
                    Text("Add Available Time", color = Color.Black)
                }

                Spacer(modifier = Modifier.height(16.dp))

                // Display Selected Times
                availableTimes.forEachIndexed { index, time ->
                    Row(
                        modifier = Modifier.fillMaxWidth()
                            .padding(vertical = 4.dp)
                            .background(Color.Gray.copy(alpha = 0.2f), RoundedCornerShape(8.dp))
                            .padding(8.dp),
                        verticalAlignment = Alignment.CenterVertically
                    ) {
                        Text(text = time, color = Color.White, modifier = Modifier.weight(1f))
                        IconButton(onClick = { availableTimes.removeAt(index) }) {
                            Icon(imageVector = Icons.Filled.Delete, contentDescription = "Remove", tint = Color.Red)
                        }
                    }
                }
            }
        },
        confirmButton = {
            AuthButtonComponent(
                value = "Save",
                onClick = {
//                    if (selectedImageUri == null) {
//                        Toast.makeText(context, "Please choose an image.", Toast.LENGTH_SHORT).show()
//                        return@AuthButtonComponent
//                    }
//                    if (customPlaceName.isBlank()) {
//                        Toast.makeText(context, "Please enter a place name.", Toast.LENGTH_SHORT).show()
//                        return@AuthButtonComponent
//                    }
//                    if (availableTimes.isEmpty()) {
//                        Toast.makeText(context, "Please add at least one available time.", Toast.LENGTH_SHORT).show()
//                        return@AuthButtonComponent
//                    }


                    val placeData = PlaceData(
                        name = customPlaceName,
                        placeImageUrl = selectedImageUri.toString(),
                        availableTimes = availableTimes.toList()
                    )

                    Log.d("PlaceData", "Saving PlaceData: $placeData")
                    onSave(placeData)
                    onDismiss()
                },
                modifier = Modifier.width(70.dp),
                fillMaxWidth = false,
                heightIn = 40.dp,
                firstColor = Color.Black,
                secondColor = Color.Black
            )
        },
        dismissButton = {
            AuthButtonComponent(
                value = "Cancel",
                onClick = { onDismiss() },
                modifier = Modifier.width(80.dp),
                fillMaxWidth = false,
                heightIn = 40.dp,
                firstColor = Color.Black,
                secondColor = Color.Black
            )
        }
    )

    // Time Picker Dialog
    if (timePickerDialog.value) {
        val timePicker = TimePickerDialog(
            context,
            { _, hour, minute ->
                val selectedTime = String.format("%02d:%02d", hour, minute)
                val times = availableTimes.add(selectedTime)
               val list =  times.toString()
                timePickerDialog.value = false
                Log.d("AvailableTimes", availableTimes.toString())
            },
            24, 0, true
        )
        timePicker.show()
    }
}

Any insights on why the times list isn’t being saved properly in Firestore would be appreciated.