Pokemon resolute what to do if the itemfinder is shaking wildly?

When using the Itemfinder in Pokemon Resolute, if it starts to rattle uncontrollably, it probably indicates its trying to alert in the direction of a powerful wild Pokémon with higher levels that is not normally encountered at the moment in the story or route.

While its generally wise to not engage too quickly or at once to these kind of Pokémon encounters that the finder alerts its best if properly prepared: leveling enough, stock on potions and revives just in case.