Hi Riz1786. My name is Lester, and I am an Independent Advisor. I'd be more than happy to assist you. I'm so sorry that you are experiencing this issue. Don't worry, I'll do everything I can to help you.
Did you purchase your Windows 11 Pro from the Microsoft Store?
Disconnect from the internet completely then try this method: Go to Settings > System > Activation. Under Update product key, click Change product key.
Use this generic retail key VK7JG-NPHTM-C97JM-9MPGT-3V66T then click 'Activate' if prompted.
If the issue persists, restart your computer and then try again.
After that enter your purchased product key to fully activate Windows Pro.
I hope this helps. If you need further assistance, please let me know. Thank you.