URP Shadow Aliasing

So, I'm relatively new to Unity, and learning proper lighting and shadowmaps in particular have been giving me a huge headache. I've searched YouTube and the forums on solutions, but it doesn't seem like anybody is having the same issue... or shall we say two issues. First, I'm getting some harsh diagonal lines on the inside of a tub model as well as underneath a transparent plane that is inset in the tub. It also happens on the tub without the plane. I've tried cranking up with shadowmap resolution and have 4 cascades, which improves it a lot, but you still get some harsh lines in some locations and some weird vertical artifacts in the back. I've also tried tweaking the lighting settings, baking lightmaps, etc. none of which get rid of those artifacts. (I attached screenshots of the issue if that helps at all)

I'm using Unity 2020.1.6f1. The models are low-poly, and the tub is basically just an extruded cylinder directly exported from blender. I don't know if it's a lighting issue, a camera issue, something with URP, or maybe something else entirely (something with the models?). Not sure if I'm missing anything or if this is an inane question to begin with, but I'd really appreciate some help if possible. Sincerely, a Unity noob.

 

Please disregard. It's 99% a model importing issue and the generated UVs. If anyone has good lighting advice I'll still take it though