Frustrating 400
It's all fun until you get stuck in a fixed range. Then you play desperately to escape from there and it backfires in the worst way possible.
Taking a serious approach is fine, but that pressure to "break out at all costs" usually just leads to bad decisions and tilt. You're better off taking a breather, reviewing your games, and switching things up - that's usually what actually helps you get past a plateau. For a break, I recommend shifting your attention to other games that do not require such concentration and strategic thinking. You can find many such games here, and I recommend giving them a try.
To me it helped alot when I didnt try to take the game so seriously, just casually playing but focusing every time. And also I played more longer games (rapid 20min) so that I would not blunder all the time 😄 then when I jumped back to 10min games it was alot easier.
I repeat: it's a board game on the Internet. Why play if not for fun? What benefit can you get? Each game of chess is complete and can be enjoyed independent of every other game of chess you play. If working on your cumulative results (rating) is fun for you, then do that. If not, then don't do that.