Please help! 4 week old won’t sleep in her bed

My little one is 4 weeks old today, she’s suffering with reflux which is getting a bit better after changing her milk to SMA anti reflux but due to the thickened formula she’s also struggling to go for a poo unless she has a suppository so these may be having an impact but she is completely uncomfortable unless she’s sleeping on me or my husband or we have her in our bed. She can be settled and asleep in my arms after a feed but will wake within 10 minutes of being put in her Moses basket, she starts to squeal and groan and squirm and then she’ll wake up. She will also do the same if we put her in her crib awake, eventually she’ll start to scream. This has only started in the last 3/4 days. Nothing will keep her asleep in her basket and I can’t hold her 24/7 no matter how much I love the cuddles. We found out after a long and restless night that if we put her in our bed next to us on her back/slightly titled to one side, she sleeps instantly. Her breathing becomes calm and not slightly wheezy, she doesn’t squirm or cry or squeal. But what am I supposed to do, I can’t sleep with her in the bed because it’s not safe but she won’t sleep in her own bed and I’m getting so tired staying awake with her that I’m falling asleep trying to care for her which is also not safe. My husband will take over at the weekends as he’s not at work Saturday and Sunday but other than that I can’t ask him for help overnight as he’s has chronic fatigue and if he was up in the night he’d struggle to drive or work and obviously he’s not here in the day so my options are limited. Any advice on how to get some sleep whilst also making sure she gets some sleep?