I think I have found out why my re-prints have not turned up, on the e-mail that they sent to me it had a box at the bottom asking if this e-mail answered my question, so I click on the Yes button, thinking that this was replying to the e-mail to say if I wanted the prints re-printed.
But checking my e-mail out box, there is no trace of it. So I have now replied to the e-mail normally. So no fault of Photobox here - just me