So today I took monty out of viv today for a handle and on his mouth there seems to be something there maybe a couple of pics will help explain am rubbish at explaining
With damage on the nose it looks to me like slight scale damage due to nose rubbing. Not serious and will shed out. Maybe just check your viv for any overly sharp bits specially around the door.
Or unshed nasal/heat pit skin - once had to help Shahi with mask and eyecaps and believe me the nostril/pit skin came out like TUFTS of stuff - couldn't believe my eyes!