Where is it not being recognised....in the Library mosule Metadata Panel, or in the Develop module Lens Correction panel? If the latter, make sure you are processing a raw file, as the majority of lens profiles are specific to raw files only.
Hi Jim - Many thanks for noticing that, my camera has just come back from a service and clean and they must have changed the settings which I failed to notice. Just done a test shot and the lens is now recognised. Very many thanks for your assistance most appreciated indeed. Mark