Rolling and getting stuck on tummy

My 6 month old has just started rolling from back to tummy all the time now and gets stuck there several times in the middle of the night. Only does this while in a sleep sack. Prior to the sleep sack we used the baby Merlin magic sleep suit which was amazing but also restricted his movement a bit. I have put him back in the Merlin suit at night now for the sake of us getting some more sleep and I’m trying to get in lots of tummy and rolling time during the day. Any tips on what to