How can I restore my previous contributions on GitHub? (GPG Key)

I created my own GPG key so that I can create verified commits using a code editor. I followed Generating a new GPG key - GitHub Docs.

However, when I added the new GPG key on GitHub. All of my previous (verified with GitHub verified signature: 4AEE…) commits/ contributions got removed. They are still verified but are not counting towards the contribution/ commit count.

Can you please tell me how I can fix this? Thanks in advance!