Under normal circumstances, it doesn't matter if you don't sign the second exam subject. As long as you are sure that you have passed the exam, even if you don't sign the report, the general test center or driving school will sign it for you. In some places, those who haven't signed yet will ask to go back and sign, as long as they have passed the exam, so don't panic. You should get the report card and sign it after the exam, not just walk away. In order to prevent the results from being invalid, it is best to sign after the exam.
Subject 2 generally refers to the subject 2 exam. Subject 2, also known as the small road test, is a part of the motor vehicle driver's license test and the abbreviation of the venue driving skills test subject. The C 1C2 test items include five compulsory tests: reversing into the warehouse, side parking, fixed-point parking and starting on the ramp, right-angle turning and curve driving (commonly known as S-bend) (there is a sixth high-speed license in some areas).