This is really common among cyclists. Sometimes it's the inner side of the patella, sometimes the outside. It's usually a simple problem of muscular imbalance, something to do with how one pedals. Your VMO is probably pulling your patella to the inside. IF that's the case, you need to strengthen your vastus lateralis. It might also be wise to temporarily raise your saddle to reduce the pressure on the patella and pedal with your toes pointing in. You probably are pedaling with your toes pointing out now. If so, reset your cleats.

I had the VMO type of patella problem years ago. I raised my saddle and pedaled in zone 1 only for 30' a day indoors while also exercising my knee muscles. That worked. It never came back. Took a month or so.

See: https://www.setforset.com/blogs/news...alis-exercises