Hi @Dhananjay_Patil ,
Once you created the portal. Did you receive the confirmation in your email stating that portal is provisioned successfully.
Alternatively you can log in to azure and go to app registrations under my owned application you can see the provisioned app with the name of "Microsoft CRM portal".
If you can see that then portal management will appear definitely. Try a hard refresh.
Plan B:
Creating templates and settings will be overwhelming. The best way would be to go to administration of the app and reset it. Then you can recreate it.
Hope it helps
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