Tail problems

[Elmo]

My mates ball python is having some tail problems as of late. His sheds have not been shedding properly at the tip of the tail everywhere else was fine. Now a 'scabby' small bit of tail at the tip keeps forming (dark red and hard, like dried blood) it is only a small bit. I was around the other day and i swabbed it with warm water and it softened it up and the scab came clean off. It left the tail then a bit injured looking and very sensitive.

He says it keeps going lik this and he is afriad it is stressing out the snake. We have upped the humidity a bit to dry and clean it and we have checked temps etc and all are fine. Any ways of cleaning this up permanently?

Thanks