I sold a pup in october the pup was ok now the owner has phoned and said
it has dry eye and it will need her eye removing I have offerd to swap the
pup but could any one help me as I have never herd of this and cant find anything in the AtoZ of dogs

Dry Eye (keratoconjunctivitis sicca) can be treated with a drug called "Optimmune".  Dogs are lucky in as much as they can have better treatment for this than humans can!

The treatment is very successful and I would certainly try this before removing the eye unless the owner let it get so bad that the eye is permanently damaged?

I had a Cavalier on Optimune for about 4 years before she died (aged 13 ) last year and with regular use the eye was great BUT you do have to keep up with the treatment .... miss it for a couple times and you will be back to square one.  Not cheap though costs about £30.00 for a tube which lasts about 3 weeks.  My vet was great about this and checked Jolly regularly to make sure she was o.k. Understand that Optimune is also available as drops if putting ointment is difficult.  Jolly also had Maxitrol drops which are steroid and these helped a lot.  Optimune alone was not as successful.  Unless the eye is damaged I can't see a good reason for removing it.