I got the game after being skilled on multiple accounts and I said this account I will not tryhard on anymore. So since my HWID and phone number were tied to accounts that were previously banned I was automatically put in low trust. I looked and looked all over the internet for solutions and I tried a few. There was only 2 things that REALLY worked for me.

First step: Queue with somebody with high trust and see where you are at. There are 2 types yellow and red. Yellow means your trust is low but not that low so the matchmaking will prioritize people with yellow same with red except red is people who are either cheating or global smurfing because somehow that's fun.

Second step: If you are either red or yellow literally just leave your game on forever. I have over 250 hours played on my past 2 weeks and that's not even as much as it can be. I farmed up from 50 hours to 700 something in a month. This did the most things for me.
Third step: Get commends I got some commends like 800 something and that helped too but I didn't see that much of a difference.

Don't try in matchmaking even in comps. I lost 6 games in a row and went from red to green just by losing those games and keeping my game open that night

Overall: To improve your trust leave your game open, play games and try to not get headshots bc headshots = cheating somehow? and also ask commend for commend to team mates. I hope I helped you have a good rest of your day!!