Can't sign app on xcode

I have an app that was built on my first mac, i got a new one and moved the code and everthing to this new mac. I exported the private key and certificate from the old mac to the new one. Tried everthing on the internet about signing an app, but it just doesn't work. Now i'm stuck in a loop on xcode. I get the message "Revoke Certificate", when i click it, xcode create a new one, but it's already expired(despites it saying that will expire in 2024), if i try to manage certificates and create from there, nothing happens. If i delete the expired certificate from keychain, the revokate certificate message comes back. Any tips?