Having a mare!

i’m a regular solo player, both Arena and Warzone. I’m having a mare. I mean, sadly, I consider myself an average Halo player but recently I’m just having a terrible terrible run. Not just poor K/D but so many of my deaths seem utter malarky. I seem to be so consistently out-skilled by other players that I’m probably giving up playing soon. My aim seems worse than ever, ranged accurate combat was never my strength but even close up I seem to be out-manuvered or out shot every time I play. What am I doing wrong? Have all the noobs left and just left all the pros?! It’s so crushing.