Cloth physics "Tangled up" when simulating?

Hello, I’m trying to add a “Flag” banner onto a lance, with cloth physics. All I’ve done is pant 0.1 stiffness onto most of it, and it ends up all tangled in itself. Parts of it seemingly shrink and jitter around. I can’t figure out how to fix this, although I theorize I just have too many faces on the banner itself.

This is the first thing I’ve made with cloth physics so I may have gone too crazy with subdivide, or not paid enough attention to the angles of the edges on the banner.

I used Blender for this, unfortunately I’m beyond the point of return since the model is done… Hopefully there’s a setting to help me so I don’t have to remodel the flag, re UV unwrap and retexture it.