Struggling with return to warzone

I used to be decent at warzone. I loved playing it and put a lot of time into it. I had almost 350 wins before new warzone came out. I took almost 2 years off because of life and now after playing for over a month I cannot get the hang of it anymore. My aim is horrible in warzone but decent in mp, I can't get into the rhythm and im not having fun. There's no silly moments or goofy squad moments it's just constant getting shit on. Maybe I'm just more tired and not as focused but I'm just sad about it. Looking for some tips or just solidarity. I miss having fun and being somewhat good lol