Is it hack?

good basically I went to three qualifiers in which I enter to play and I'm very good in the first minutes of play and suddenly I start a lag from 500 to 3000 and of course it happens that I lose the game but the most and what is not I can explain is that I never have lag in normal or ranqued until two days ago and I've been playing in na for a year since I'm in Colombia so I wonder is some hack? why I go to play other ranqued and it does not happen to me I would appreciate if you can check what the hell is going on because it is disgusting to have to fight to get out of a low place so that now this happens to me and I repeat in more than a year I do not have lag and my internet is very stable