Same here. Yesterday ps4 single player. Three times but I don’t have to restart the game. Just close the message and then it was gone. Pop up few minutes later but two times but then don’t came back again.
So apparently some people saw this as early as last year during the Grave Matters Event in SOLO mode in Conan Exiles.
I can confirm that so far no amount of restarts or Reboots on console will remove it. So something in SOLO play is triggering it currently on my PS4.
I can also confirm that hitting the acknowledge button removes pop-up until the next occurrence of pop-up, with no visible effect to game play, unless it happens at a crucial moment, in which case you will die.
Growing pains eh, if this was the most annoying thing happening in Conan I would be pumped.