Marley still has his baby fangs top and bottom but also has his adult fangs half way through right next to the first set :-(

Often happens - if they don't come out of their own accord the vet will need to take them out for you.

This happened with one of my litter I told owner to give him plenty of bones to chew sure enough they came out a couple of days later. If it persists then a trip to the vet is needed.
Angela

I had this too,  I was told to give a whole raw carrot to chew as this will help the teeth to come out naturally.