GPG key created with sudo cannot be used to sign Git commit

When I attempt to create a new key for Github with this command:

gpg --full-gen-key

I keep receiving this error:

gpg: no writable public keyring found: Not found
Key generation failed: Not found

So I added sudo in front of the command and the key was created. Then I added the key to Github and set the signing key to Git. However, when I tested the key with a new commit, it gave me this error:

error: gpg failed to sign the data
fatal: failed to write commit object

I assumed it's because I used sudo but I cannot create a key otherwise. It keeps giving the public keyring error every I use gpg alone. Any clarification on this is appreciated.

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