Hi Deepak Vaswani,
Thank you for contacting Microsoft!
As announced, we are no longer making feature updates to Exchange Web Services (EWS) in Exchange Online, and we have advised developers to transition to Microsoft Graph.
Please find the referenced links below with the requested information about migrating from EWS to Microsoft Graph:
EWS (Exchange Web Services) to Microsoft Graph Migration Guide Series
Identify applications using Exchange Web Services (EWS) APIs
Hope this helps.
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