Service intervals on a 2017 touran rline

[Jamesj]

Hi I have recently bought a 2017 touran 1.5 petrol dsg. It came from a VW dealer and is under extended warranty. 

It has recently come up with the service required light on the dash. VW UK say it should have been serviced but dealer are saying its on a 24 month interval. Last time it was serviced it wasn't serviced by vw and when I rang the garage who serviced it they said its due now. 

Dealer are adamant that its 24 months and refusing to service it, instead they are saying they will turn off the service light... Can they just say its on a 24 month plan even though it hasn't had the necessary service previously. When I had a passat you had to pay forca major service to qualify for the 24 month interval. 

I personally think it's the dealer talking nonsense to avoid servicing the car, or am I missing something?

Thanks in advance

James