Need help! Damage fell off at random, I think?

For some reason after playing through a GR35 I lost most of my damage, I’m currently playing a Witch Doctor and using the hell tooth set and paragon 215, I’m a newb at building in Diablo but I know how to work stats pretty good and I’ve been going for a build and collecting all the pieces, other than that my damage numbers were usually something around 10b to 28b now I’m still hitting the same numbers but not doing nearly as much damage as before I’ve checked everything but I haven’t changed my build one bit, my character has transitioned from seasonal but idk if that affects anything, Help please this sucks…. Ps4 btw