what can u do to get a 3 week old with acid reflex to go to sleep

Swaddle him really well and rock and pat or stand up and sway... it worked for mine

I have a girl

and I tried that when we were still at the hospital and it didn't work

Get the rock and play sleeper. Their head is safely elevated so it elimates their acid reflux when they sleep, so they sleep longer. All my daughters had it and they all slept in there until they were 5 months

we have a swing