My provider failed, now I got another leaving

My provider decided to stop gigng me internet.
I left the game for some round but I managed to come back after recetting everything.

I played a decend game but still got banned (what is acceptable), however now my leaver buster is extremel high because I “left” a game we surrenderd to early. I am afraid if this happens again I wont be able to play at all for a long time.