I've looked up a little on this but haven't really found anything that makes much of a difference or helps, so I was hoping somebody on here might know of something that would.

From what I've read it's usually due to things with form, like gripping too hard, or your elbow not staying stationary, or too much swaying motion. But I always make sure to not grip hard, I make sure to keep my elbow steady during each rep and to not let my body sway a bunch, but I still always start feeling a lot more sore in my forearm/inner elbow area long before my biceps get worked very much.

(Btw I know this isn't a bodybuilding forum lol but I don't visit any other forums and just thought since it's exercise related it would be okay to post here, so hopefully it is!)