Hi Shamim,
I have a custom field type “number” labelled “Total Cost”.
It does not have a “required” property.
However, when I try to send a message with this field left empty I get the following error:
Error: Total Cost is not a valid number.
The field needs to be optional. How can I achieve this?

$fields[‘cus_fep_textbox26’] = [
‘type’ => ‘number’,
‘where’ => array( ‘reply’, ‘shortcode-newmessage’, ‘newmessage’ ),
‘priority’ => 6,
‘label’ => ‘Total Cost’,
];

Thanks for your help.