Combo's in trials not hitting opponent

Hello, I don’t understand why during the trials, my combo comes out but some attacks just go through the opponent, doing no damage to them even though it’s hitting them.

For example maximum’s #9 trial, my giant laser at the end hits him while he’s falling, but it’s not completing the trial because for some reason he takes zero damage.

With king in trial 6, I can do the entire combo perfectly if I do them in 2 steps. But when I try to complete the first part, my DP kick sometimes doesn’t even hit the guy after the ex fireball + normal fireball. It’s like the attacks don’t hurt the opponents sometimes. I get this with a few characters, this is the only reason I can’t complete the 200 trials.