AppleScript-created reminder not visible

For instance:

tell theRec to make new reminder with properties {due date:theDate, schedule:monthly, interval:2}

This reminder will be attached to the record correctly.

Back to AppleScript again, and this :

get properties of reminder of theRec

gives:

{class:reminder, week of month:no week, alarm:no alarm, interval:2, masc:0, day of week:no day, schedule:monthly, due date:date "woensdag 24 januari 2024 om 1:56:00 PM", alarm string:missing value}

But it is not visible in the inspector.