Being able to cast while i am stunned

[fflleexx]

WoW Freakz spell link: any spell or movement
Bug description: I play on this server since it got opened. Since 7.2.5 i notice extremly rare that in PVP it happened to be stunned and still be able to move or cast, also i notice this on other players too but i haven't paid attention because i usually don't care about bugs i just play for fun. Because of this thing i got banned and i tried to explain and got banned even more. I will tell here too that i don't do anything to make this happen i just play like i do usually. I want you to search for the problem and prove that i did nothing or exploit of something. Thank you!
Proof: https://prnt.sc/qe1khe