Baby laying face down while sleeping

Lauren • Had my sweet girl 02/22/20 - 5 weeks early due to rare genetic disorder💗 Had my handsome man 09/30/22 - 3 weeks early due to low birth weight💙

My daughter is almost 6 months. She’s started rolling in the middle of the night. Sometimes she rolls face down into the mattress and it really freaks me out that she’s going to suffocate. I know she can lift her head but when she’s half asleep she just stuff her face into the mattress and just leaves it there and I’m terrified!

Is this normal? Is there anything I should do?