Hisense 58R6E3 Roku tv flickering on lower half of screen.

So I was getting a ton of weird lines across the tv, and the screen would freeze that way, so I did some research and replaced the tcon board on this unit. Now it works for the most part, except I have this flickering which only happens on the lower half (see video). It seems like when I first put the new tcon board in I didn’t get any flickering for the first hour or so, so not sure what could be going on. Any suggestions?