About 74LS74 and 74LS00 constitute phase detector related issues

Good day, amazing people
74LS74 and 74LS00 are used to form a phase detector. (tips: the datasheet)
In the simulation results, one output of the two outputs is a square wave signal with phase difference and one is a periodic pulse signal, and the frequency of the two signals is the same. However, in actual debugging, there will be situations where two signals alternately appear. I hope to get some advice!
Good Listening

What are you trying to do?