Unable to stack row on top of row using jetpack compose

I have the following code currently:

Edit 1:

@Composable
fun CustomerProfile(
    customerProfileViewModel: CustomerProfileViewModel = viewModel()
) {
    val snackbarHostState = remember { SnackbarHostState() }
    val scope = rememberCoroutineScope()

    Scaffold(
        snackbarHost = {
            SnackbarHost(hostState = snackbarHostState)
        }
    ) { _ ->
        Row(
            modifier = Modifier.fillMaxSize()
        ) {
            Row {
                HeaderPlate(
                    scope = scope,
                    snackbarState = snackbarHostState,
                    firstName = customerProfileViewModel.getStateValue().customer.firstName,
                    lastName = customerProfileViewModel.getStateValue().customer.lastName,
                )

                CustomerDetailsList(initialiseCustomerDetailsList(customerProfileViewModel))
            }
        }
    }
}

This creates the following view:

However, what I want is to have the grey rows below the blue header. I'm a little new to compose still so any help would be appreciated!

Thanks!

Edit 1:

I've changed the code to what you've suggested and now I get the following:

As you can see, the list has entirely disappeared.

You should use Column instead of Box:

@Composable
fun CustomerProfile(
    customerProfileViewModel: CustomerProfileViewModel = viewModel()
) {
    val customerDetailsList: List<CustomerDetails> = initialiseCustomerDetailsList(viewModel = customerProfileViewModel)
    val snackbarHostState = remember { SnackbarHostState() }
    val scope = rememberCoroutineScope()

    Scaffold(
        snackbarHost = {
            SnackbarHost(hostState = snackbarHostState)
        }
    ) { it ->
        // ... Use Column Here ...
        Column(
            modifier = Modifier.fillMaxSize()
        ) {
            HeaderPlate(
                scope = scope,
                snackbarState = snackbarHostState,
                firstName = customerProfileViewModel.getStateValue().customer.firstName,
                lastName = customerProfileViewModel.getStateValue().customer.lastName,
            )

            LazyColumn {
                items(count = customerDetailsList.size) {index ->
                    val customer = customerDetailsList[index]
                    CustomerDetailsCard(
                        icon = customer.icon,
                        title = customer.title,
                        value = customer.value,
                    )
                }
            }
        }
    }