Hi @Rao Safdar Iqbal ,
Thanks for reaching out.
As per my knowledge and documentation, This is by design. To keep the meeting link, do not update the body in the request, and it should work.
Before updating the body of an event that has been set up as an online meeting, be sure to first get the body property, apply the appropriate changes to the content, and preserve the meeting blob for online meeting. Inadvertently removing the meeting blob from the body would disable meeting online.
The issue is happening because of a fix / feature that has been implemented on outlook end where it is cleaning up the online meeting properties if the Teams meeting blob is removed from the body.
I am able to replicate it. As a work around you can use PATCH body by writing the URL of TeamsMeeting into the body.
Hope this helps.
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