Ranked Decay?

So right now I think I might be having a bug where the client is telling me that I'm going to decay in ranked if I remain inactive. I'm currently diamond 5 48 lp. That 48 lp has come from 3 games that I have won in the past 8 days, yet it tells me that I have 5 days before I start decaying. Does anybody know if this is just a bug or what? I've been trying to play less league and don't want to be forced into playing just so that I don't decay. I was also pretty sure that you only need to win a single game to stop decay, yet I've played and won 3.