Should I be concerned or is this normal?

My LO started rolling tummy to back at 2 1/2 months old. She did it all the time. Now at 4 1/2 months she learned how to roll from back to tummy. She gets lots of tummy time, but she has completely stopped rolling from tummy to back. She’s now a little over 5 months old and she will not roll from her tummy anymore. She constantly rolls from her back onto her stomach just to ream until we flip her back over or pick her up. I know babies will focus on something else when they are learning something new but it’s been quite awhile since she’s rolled from her tummy. I don’t know if this is a normal thing. She has started cooing and making new sounds lately, along with severely teething. When do I become concerned and is anyone else’s baby doing this???