[MENTION=97077]iserith[/MENTION] has some good advice upthread (as always).
My answer is a bit involved, but it amounts to craft better (i.e. clear but not give-away) clues as a DM. Actually, this advice is true regardless of high passive Perception.
A lot of D&D example – in the book and streamed on Twitch - have Perception (whether passive or active checks) revealing traps, secret doors, and other stuff like that. The DM says (or the book implies the correct response is) "you see a tripwire" or "you see the outline of a pit trap" or "yes, there's a secret door in the alcove."
Personally, I find that approach really damaging to immersion and involvement in the game. And it's a far cry from challenging the players' logical/creative thinking. As soon as you say "you see the outline of a pit trap" you've taken away the mystery. There's no threat now. Not really. Unless you're throwing in monsters that are imposing forced movement or using one of the horribly meta-gamey Grimtooth's Traps.
Instead, I want to give the player a clue that alludes to the presence of something unusual, but doesn't make it clear what that is exactly.
For example, I might say to the 21 passive Perception PC's player: "You notice signs of weathering as if from shuffling feet around the edges of the central flagstone of this passage."
A savvy player is going to wonder whether the flagstone could be a trap. Maybe they'll wonder if it's the flagstone that's trapped or the space to the side of it.
I do this the other way around. The clue is embedded in the "boxed text" if you will (Step 1: DM describes the environment). This is my telegraphing - everyone gets it for "free."
The "Yes, there's a secret door in the alcove..." or whatever comes after I know there is a character engaged in the task of searching for secret doors at the exclusion of other tasks and I have resolved any uncertainty as to the outcome with a game mechanic.