Try to make something unconventional for once, or a bit "viral". Your account might not be shaddowbanned but victim of the algorithm. For example, everything works in cycles. You get a bad video, then IG will lower your reach, then you get another bad video, it continue to do so, your average view and likes is down.
So on one of my 100K+ account, I took some break, came back, my average was like 30k+ per reel, then, I kept going, kept working on having the best possible content, 10K average, then I still kept going, then one video went nuts, like 500K, then next 1M, then one 3M, then one 8M views... so keep going, take a few days off to make sure its not a shaddow ban, and keep going, focus on quality, look what works in your niche, try to add some open talk, or controversy, like make people comment so it's viral more. You always need that 1/2 vid that will boost everything following the 80/20 rule, a lot of your videos will suck, but that 20% will bring the best results.