I've had no problem like this on the PC version, so it seems to be a PS5 issue. When I tag enemies, the fifth enemy I tag doesn't get the chevrons over their head. Instead, the chevrons appear next to the chevrons of the previous enemy I tagged. If I untag the enemy, only the right chevon disappears. If I tag an enemy this way, it still acts as though it's tagged (being highlighted). Any enemies I tag after that don't have chevrons show up anywhere (or any indication that they've been tagged) but are still highlighted.