Hi Chintan Gajjar,
Thanks for your post. Please understand that this is an improper use of NAT in Hyper-V or any other like App such as VMware. NAT is for DHCP and IP addresses will change occasionally. If you wish to have a Static IP address, you can set up an External Network Switch in Hyper-V (so Bridged Network) and then the Guest will get an IP on the Host Network Router. That can be Static if you wish.
Best Regards,
Ian Xue
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