120000km Service

I have a service plan policy with 360-Plus/Liquid Capital for my 2007 VW Polo 1.6 Trendline. The policy has been existing for about a year and my first claim was not addressed in a manner that satisfies me as a client. They have refused to authorise campbelt replacement at 120000km service. They say they are unable to authorise campbelt replacement at 120000km as it must be changed at 90000km service. I have consulted my service schedule that comes out with the car and have made contact with VW South Africa, who also confirmed that it is mandatory to have the such belt checked at 90000km, thereafter every 30000kms until it is recommended for replacement. I can confirm Campbelt was checked during my 90000km service and at the time it was found to be still in a good condition