Galaxy watch 4 black screen

I have a galaxy watch 4 that was working fine until one day it just went black and won't turn on. I thought the battery may have went out and so i replaced it. it brought some life back, cause now it will vibrate if I try to force a restart but that's all it will do. The watch does not indicate that it is charging, but the charging dock lights up to indicate charging. I have also got a replacement charge coil incase it went out but that didn't solve this issue either. I've checked and cleaned all the connections. any suggestions?