@Mohammed Abdul Majeed Thanks for posting your query on Microsoft Q&A. Sorry that you are facing this issue.
Here are few things you can try:
You can force Update the Network Interface with Azure CLI, PowerShell, or through Resources.Azure.com
-Using Azure Cloud Shell:
CLI Update Network Interface: https://learn.microsoft.com/en-us/cli/azure/network/nic?view=azure-cli-latest
-Using Resources.Azure.com:
Find the Network Interface through Subscriptions > (Subscription Name) > resourceGroups > (ResourceGroup Name) > providers > Microsoft.Network > networkInterfaces > (Interface Name)
Edit then PUT to force the resource to update with Azure if it's stuck in a deletion, or updating state.
Reference post: https://learn.microsoft.com/en-us/answers/questions/141385/cannot-delete-resource-group-because-of-network-in.html
However, if none of these suggestions work for you, I would recommend creating a support request since the resources would then need to be removed from the backend with the help of support engineer.
Let me know in the comments if you have any questions or if you do not have a support plan to create a support request. I can help you create one. Thanks.