unable to handle request on form submission

Hey,

In my pod (form on frontend) I have checkboxes which, when checked, creates an item in another pod through pods_api_post_save_pod_item. I have build my code like this:

$non_actief = $paard_pod->field('non-actief'); //checkboxes
$add_dossier = $paard_pod->field('add_dossier');
$verwijderen = $paard_pod->field('verwijderen');
		
if($non_actief) {
	delete_post_meta($id, 'groep');
	
	if($add_dossier) {
		$data = array(
			'paard' => $id,
			'author' => $user, // User ID for relationship field
			'opmerkingen' => 'Non-actief gezet',
			'verschijndatum' => date('d-m-Y')
		);
		$dossier_pod->add( $data );
				
		$paard_data = array(
			'add_dossier' => false
		);
		$paard_pod->save($paard_data, $id);
	}
}elseif($verwijderen){
	$paard_verwijderen->delete($id);
}else {
	if($add_dossier) {
		$data = array(
			'paard' => $id,
			'author' => $user, // User ID for relationship field
			'opmerkingen' => 'Terug actief gezet',
			'verschijndatum' => date('d-m-Y')
		);
		$dossier_pod->add( $data );
				
		$paard_data = array(
			'add_dossier' => false
		);
		$paard_pod->save($paard_data, $id);
	}
}

It all works fine but when I check the box for ‘non-actief’ it shows an popup saying ‘unable to handle request’ (wp-admin/admin-ajax.php?pods_ajax=1&action=pods_admin 500 error) but the code has run and worked! It also only happens with that particular checkbox. The others work fine.

I can’t seem to find what happens here? Could someone help me?

Thanks,
Mart

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