Random champs break my blocks (no heavy attack or apoc)

CritCap

I’m playing 5.2.4 and I parry the first time and he heals and nullifies it (masochism). But during the cool down I parry again and he doesn’t get dizzy (it says parry on the side) and breaks my block randomly! Please give me a reasonable explanation or let me know if u have anything like that too!! If I get enough replies of people having that issue I’ll do a poll to whether KABAM should fix this!

Sktd3

Which champ where you fighting against
Or is it through out the quest,

It has happened to me but it is input droppage on my side, like suddenly my attacks would stop