Hi Bahaa,
Thank you for more information on your concern.
In the Google Ads API's perspective, and as mentioned
here, duplicate conversions are allowed and would not return errors. However, only the first instance will be recorded and the succeeding duplicates will be ignored.
Since you are also using a different source (Google Analytics) then I would recommend that you verify this scenario with the Google Ads Product Support team via this
link, for further guidance. I hope this helps.