Why can't i sell an item for the price i want to sell?

I want to sell an item for a price, 557 coins but the game change it back to 542. why?
I have an pending selling offer of the same item at 557, but this time it doesn’t let me.
I don’t mind to wait until it gets purchased by someone.
But this time the game doesn’t let me.

Screwy behavior of the price corridors…

They buying side is just as bad, I’ve seen plenty of items get locked where the price to buy it isn’t even available. lol