Crib transition

My 4 month old wakes up every 45-50 mins on the dot in her crib but the second I give up and take her back in her rock n play she’ll sleep 8+ hours straight

How long does it take for them to get comfortable enough to sleep longer in their crib?! It’s been 2 weeks!

And I put her down drowsy and she falls asleep on her own but when she stirs at the 45 min mark she then can’t put herself back to sleep with out me soothing her (generally just put my hand on her chest or let her hold my hand) and she’ll fall back asleep eventually.

She has also been sleep deprived because of trying to get her to sleep in her crib it’s really cutting out of her sleep time 😩 and mine lol

Just venting idk what else to do