HI Thank for asking to HCM Bed wetting Nocturnal enuresis much is common among the toddlers which goes away as the child becomes older, but at the age of 21 it is most unlikely, before to come on common cause of this, I would suggest you for certain investigations first complete urine analysis, second Blood sugar test, third Usg of whole Abdomen, if these turned negative then you try bladder training, in day time when you feel like passing of urine, just hold it down as long as you can then go for urination just do it every time, do not drinki water before going to bed, not just water but any liquid, this will help you a lot, if it fails then try Amitriptyline ( antidepressant ) one tab. at bed time. have nice day.