I keep receiving TikTok verification codes

Don’t engage. Also, change your password ASAP. Someone might be trying to hack into your account, probably to try to make money selling it. If you change your password you should be ok.

I know that these are expired, but never send codes or screenshots of a security code to anyone, especially not Reddit.

Someone is likely trying to access your account and keeps triggering 2 factor authentication. If you ignore them all, scammers will get bored and move onto another account eventually.

You are being hacked.

Happened to me this morning too. Changed my password asap