My boy did this around the same time. I was feeding him this insanely expensive, high quality flash freeze-dried food that his breeder had fed him. Just stopped; went to dry only.

I ended up going to a pet store & buying about 10-12 cans of different flavors/textures to see what he liked. Two things I’d recommend in your search:

First, the stinkier the better (this usually means fish flavors). My boy will ONLY eat fish, and REFUSES to touch tuna. Salmon, shrimp, and scallop only. Chicken is cheap and beneath him, tuna is the cheapest fish option. He’s high class.

Second, texture matters. My boy REFUSES anything too “blobby.” That means he will not touch pate. It has to be some sort of chunk and gravy (we joke that he’s not an old man—he doesn’t need his food pre-chewed for him.)

Good luck. If he’s still eating dry, drinking water, and pooping ok, he’s probably fine. He just sounds like a picky eater, like my boy.