Suggestions pls to help 1 yr old sleep longer than 30 minutes at least once a day .

He he only sleeps once a day for 3 months but wakes after 30 minutes and if I don't manage to resettle him then he is so grumpy .
He sleeps well at night but not during the day .
Sometimes I feel forced to walk him in pusher for hours to try to get him to sleep more if I can't resettle him
I'd love suggestions pls
thank you