Hey moms, question?

Hello I have a 4 almost 5 year old who has been potty trained since 2, however I cannot get him trained through the night. I have tried a potty alarm, waking him, no drink after 7, earlier bed time and the list goes on, I have even spoke to doc and no luck... any tricks, tips or advice. He wants to learn so bad and really tries (he gets so embarrassed when he has to wear night pants, I always try to tell him it's okay he's learning) I feel so bad for him and the washing machine, lol being silly 😊 but serious... HELP please