Rating zeroing bug

Hello, ran into the following bug.
After playing in a league where I am in the 5 bronze and have 400+ points, after closing the window with the statistics I find that my rating was nullified, and for the game gave 75 points. So now instead of 400 rating points I only have 75.
I was given 25 points per game when I won, or deducted. Below 200 rating, they subtracted and added 15 points. And then after I won the game I lost 400 and was given 75.

I’m frustrated because I spent 200+ games on a 400 rating in 5 bronze. After that I did not play, it happened today. The point of playing in the league is lost if the result can be lost on its own.

Please return my already low rating. Server Europe, nickname BalancePoint.
Thank you.

Bronce 5 is a special place to be in. See following news from 2019 for a rough explanation: