How to increase behaviour score?

as you can see I somehow tanked it so much inbetween 15 games. The games were years ago and now i cant even play on my own server (australia), i have to queue on SEA which gives bad ping.

How tf did i get 23 reports in one game back in 2016.

anyways it only updates every 15 games and climbs by like 500. I need 4500 more to be able to even find a game on my home server, unless the Aus scene died somehow and this is the reality.