Hi @Omkar
Unfortunately, reserve ip address or static ip address to vpn client isn't supported.
You can send your feedback to Microsoft:
https://feedback.azure.com/d365community/
There is already an idea for this, you can add your comments:
https://feedback.azure.com/d365community/idea/639028dd-8926-ec11-b6e6-000d3a4f0789
Best
Get in touch if you need more help with this issue.
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