Apologies for the re-submission. I'm re-submitting with sample code, since I can't delete my previous request (forum throws an error).
Can you tweak this code so it works? Here's what it needs to do..
This needs to create/update users and assign multiple user roles from a checkbox field. It does not. It creates/updates a user with the role set in the form action, ignoring the values in the checkbox field. They're custom roles and they're set up correctly in the form with separate values.

form key: custom-roles field key: 'custom_user_roles' valid roles: 'custom_role_one', 'custom_role_two', 'custom_role_three', 'custom_role_four'

-- CODE SNIPPET --

function assign_user_multiple_roles($entry_id, $form_id) {
// Check if the form ID matches the target form
$target_form_id = FrmForm::get_id_by_key("custom-roles");
if ($form_id == $target_form_id) {
// Get the user ID from the form submission
$user_id = isset($_POST['frm_user_id']) ? (int)$_POST['frm_user_id'] : 0;
// Make sure the user ID is valid
if ($user_id > 0) {
// Get the user object
$user = get_userdata($user_id);
// Check if the user object exists
if ($user instanceof WP_User) {
// Get the selected roles from the form submission
$selected_roles = isset($_POST['custom_user_roles']) ? (array)$_POST['custom_user_roles'] : [];
// Define an array of all valid roles
$all_valid_roles = ['custom_role_one', 'custom_role_two', 'custom_role_three', 'custom_role_four'];
// Clear existing roles
foreach ($user->roles as $role) {
$user->remove_role($role);
}
// Loop through the selected roles and add them
foreach ($selected_roles as $role) {
if (in_array($role, $all_valid_roles)) {
$user->add_role($role);
}
}
}
}
}
}
// Hook into Formidable Forms after entry creation and update
add_action('frm_after_create_entry', 'assign_user_multiple_roles', 30, 2);
add_action('frm_after_update_entry', 'assign_user_multiple_roles', 30, 2);