Command blocks will not work when you change the time of day.

Just 5 minutes after finding the sand glitch, I found another one. I Was experimenting a little more of my discovery yesterday of how to make Custom Jockeys. Before, I Made a Pillager Jockey. (And it worked.)Then wanted to make a Stray Jockey, set it to night, (So It wouldn't die,) Then nothing. It has worked in the past and i've done it correct all the time. So, something's wrong.