Hi Avneet Dabas!
Does this issue persist all the time?
Do you have any operations before this issue occurred?
It recommends you try to check if you meet these pre-requisites in AudioCodes SBC.
*AudioCodes SBC should running at least version 7.20A.250 or above
*SBC Sessions and Microsoft Teams license should be installed
*Make sure you allow the following ports that the SBC uses

For more details about detailed pre-requistes in SBC, you can refer to:
https://www.lee-ford.co.uk/teams-direct-routing-with-an-audiocodes-sbc/
Note: Microsoft is providing this information as a convenience to you. The sites are not controlled by Microsoft. Microsoft cannot make any representations regarding the quality, safety, or suitability of any software or information found there. Please make
sure that you completely understand the risk before retrieving any suggestions from the above link.
Best Regards,
Jimmy Yang
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