On running Github Copilot: Collect Diagnostics (Ctrl+Shift+P) in VSCode, I found out that another account was being used. What worked for me was signing out of this account that did not have Pro subscription. My personal account has it and I signed in again using that. Now, copilot is using that account itself. You might have only one account connected, but github copilot might be connected to another one that you might have possibly used before.