Screen not working after battery replacement,

Replaced my 6Plus battery with the iFixit kit, worked a charm. Phone restarted afterwards with no issue, data good, apps working. However after a few moment some of the touch screen functions were not working and then the screen completely died. I replaced the original Apple battery to see if that was the issue but zero response and zero change. I did look if the screen connectors were damaged in some way but nothing was visible.