Baby’s belly button 5 weeks

My baby girl will be 5 weeks on Friday, her belly button still hasn’t completely healed. It doesn’t appear infected, it’s not like oozing or smelly or red around the outside but it’s not healed! Every-time a scab forms it either comes off with the nappy or her vest and we are back to square one. I’m going to contact my HV (health visitor) UK tomorrow, but has anyone else experienced this?