New hidden grotto bug

so i was looking for special types of poke balls in grotto’s, when i was on Route 3, i found a Sawk and thought: “hey, i don’t have one of those yet, let’s catch it for my dex”. so i caught it, then when i arrived at Route 4’s Hidden grotto, there was nothing, while it had reset already, i interacted with the line in the middle to look for hidden items, but when i interacted with the spot 2 steps away from the upper wall, i got into a battle with the same sawk i caught on Route 3, while Sawk don’t even appear on Route 4’s hidden Grotto, only Squirtle, Poliwhirl, Panpour and Delta Sunkern appear there