Update 2: 1. Removed all automatically generated certificates. 2. Created a new empty project with a new bundle id and manual signing for release. 3. Setup xcode cloud. 4. Manual build & upload through xcode succeeded. 5. Xcode cloud build & upload failed with the same "Invalid Signature" error.

Update: I created a new bundle id (not an empty project unfortunately, I'll do that as well) and got the same "Invalid Signature" error as stated above.