Combat turns and damage are being applied twice

In combat, when I attack, everything is handled properly. The attack roll, damage roll, on-hit effects, all of it. But when I end my turn, and the next NPC’s turn gets processed, it re-applies my damage and effects a second time, effectively making me do double damage.

Also, one narrative turn after combat ends, it reapplies the final damage, narrates the fight ending, and grants us XP a second time.

I’m all for extra freebies, but this is probably worth looking into.