Owlet smart sock

Hi! Just purchased the owlet smart sock after a 5 day hospital stay with my 10M old. I suffer from extreme anxiety so hoping this brings me some peace of mind. Wondering if any mamas out there can confirm what baby’s resting sleep heart rate is for a baby between 8-12m +. When I check the guidelines, it says my LO heart rate at rest should be are 90bpm yet his flutters around mid 70’s to low 80’s. Wondering if it’s normal or sock accuracy.

Also, what has caused your red alerts , good to know in case it ever goes off