Clio 200 CUP unable to select 5th or 6th gear?

I sold my Clio 200 CUP a few days ago and the new owner has just contacted me to say today he was unable to select 5th or 6th gear. 1st, 2nd, 3rd, 4th and reverse are all ok but he cannot select 5th or 6th while stationary or while driving.

There's no crunching, whining etc but he says he can't get it into 5th or 6th. The cars not missed a beat while in my ownership so I'm completely miffed at why there is an issue now.

Has anyone else had any experience of a similar issue? The only thing I can logically think of is possibly either a gearbox mount, or a linkage issue?

Any help would be much appreciated as I can pass the information on to the new owner

cheers
 
All sorted, apparently it was a gear selector gromit that had popped out of position, it has now been put back in the correct position and working fine!