Scrip condition not for Reminders

Hello,

We use a RT scrip to check on close if a Custom filed is empty. If the Custom field  is empty, the script reopens the ticket.

Condition:  On Resolved

Custom action preparation code:
if( ! $self->TicketObj-> FirstCustomFieldValue( 'FieldName' ) ) {
$self->TicketObj->SetStatus('open');
}else{
$self->TicketObj->AddCustomFieldValue(
                    Field => 'FieldName',
                    Value => 'true');
}



Now we have a problem with the reminders: When I close a reminder the scrip reopen it.

Is there a way to prevent this?

Thank you,
Tobi

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