Sign an unsigned xcarchive (or ipa)

I have to sign an unsigned .xcarchive or .ipa file (I have both, I can choose the best solution). This app contains an extension. I have both the provisioning profiles of the main app and the extension and I have the Distribution certificate installed in my keychain. Everything I tried failed, I used iOS App Signer, I tried doing things manually, I guess I'm missing something. Do you have a solution? Thanks.