Baby keeps sitting up when falling asleep

Brittany

I know he’s tired AF but for some reason when we put him down he just wants to sit up and wander around his crib anyways, for like an hour! And he’s so tired he starts burring his head in the blankets while sitting up, sometimes hitting his head on the crib and crying :/

I pay him back down multiple times, he rubs his eyes and yawns and he rolls over and sits right back up again. Literally for like an hour. What can I do? Is his bed uncomfortable? How do I get him to stop fighting his sleep?