Anyone else!?

My 15 week old has totally unlearned everything we worked so hard on!! He can’t stay asleep while napping on a flat surface anymore all day.. he’ll snooze on his boppy pillow (while we’re watching) or in the car but the second I put him down flat in the pack and play his arms flail and he wakes up!! No matter how many times I try or shush him etc.

And at night we’re back to waking every two house after his initial longer stretch of maybe 4 hours. Anyone gone through this and gotten to the other side!?