Some baby's don't roll but do everything else like crawl, walk etc
The best advice I can give is babies developed differently & some don’t roll at all. They just jump too crawling or walking! I have twins so I really see how babies develop at different pace than one another. My son rolled once around 4-5 months & wouldn’t roll over again until 6 months. My daughter rolled once at 5 months & has been unstoppable ever since. Another example is how my son can sit up on his own (they are 7 months) but my daughter has yet not.
Each baby have different paces for each milestone. Just keep trying as you always do, and soon he will be rolling ☺️
I'd say 5 months is still early so don't worry, my LO is nearly 5.5 months and started rolling yesterday, he struggled too for ages and then just suddenly got it and now all he does is roll anywhere I put him. He'll pick it up when he's ready! 😊
My little girl didn't roll until she was 6.5 months. She's now 9 months, crawling, pulling herself to stand and generally doing really well. Don't sweat it too much, they go at their own pace, but they do get there! X