No deposit code dead?

Tried using that no deposit code floating around yesterday and it fizzled - just got the classic “invalid or expired” pop-up and not even a crumb for my trouble. Kinda feels like these codes last about as long as a cold cup of tea I forgot on the window sill. Every time I spot one on a promo list, it’s already on life support. Not even the live chat folks knew what was up when I poked them, just got the ol’ canned “subject to availability” response.

Has anyone actually managed to land something with these lately, or is the game now about speed and luck just catching an active one? Wondering if the promo folks are purposely setting codes to “blink and you’ll miss it” mode or if it’s just more of us checking and testing every door at once. Anyone got a trick for sifting out duds faster, or is it just rinse and repeat until it works?