Hey @EmanWah
If you are trying to set the recurrence for 1st day every month, you can see the below configuration:
You can put the date format as highlighted.
Hope this Helps!
If this reply has answered your question or solved your issue, please mark this question as answered. Answered questions helps users in the future who may have the same issue or question quickly find a resolution via search. If you liked my response, please consider giving it a thumbs up. THANKS!