Simple question(like true/false on stupid tests)

Hello. I have one easy question:
I have the error message: “Unable to build chain to self-signed root for signer “Apple Development: Aidarbek Sultanbekov (sthhere)” Command CodeSign failed with a nonzero exit code”, after I tried to run the app on my iPhone. Is it a problem with the certificate?

Have you set up an Apple developer account with Xcode?? (Even a free account is fine, you don’t need to pay just yet)

Try Cmd + Shift + K to clean the build folder too

I tried this, it didn’t help(but only command+shift+k- not capital). I think there are some problems with the certificates, identifiers or provisioning profiles. Can you explain me why cannot I delete some unreliable certificate from the system in keychain even if I didn’t create it at apple developer program or revoked it or created a long time ago when I didn’t have the apple developer program?