Check gear lever position message

Car is about a year old and under warranty, occasionally on changing into 6th I get a beep and the message "Check Gear Lever Position", adaptive cruise drops out, move the lever out of gear and back in to 6 and reset cruise and all is well.  It ONLY happens in sixth and ONLY when changing into sixth.

Note: if the engine speed drops and it wants a lower gear I get the "please change gear" message so it isn't that I am in too low a gear.

It wouldn't start (Battery was flat) a couple of months ago and called Skoda Assist out and the technician thought it was one of the gear lever position sensors in the base of the gear lever, reported this to the dealer when it went in for them to check the gear lever position issue.

Dealer could not reproduce the fault and is basically saying it is my fault for being in the wrong gear but that gives a different message.

Anyone else experienced this?