NO HELP

I took an maintenance plan with Innovation group when i bought my second hand car a VW Polo Vivo in 2013 November, so I've been getting problems with it and try to get help from them through VW Queenstown as my car is being serviced by them. Its about 3 times VW Queenstown been sending them the Quote for the repair that they need to approve but their excuse is that i once took my car late for service and the Service Advisor from VW Queenstown has been trying to explain to them why, I once took my car for service in advance with 5000 km before and that 5000 km was added on the coming service so instead of waiting for 150000km i waited for 20000km and took again for service and VW find few thing to be fixed and the quoted was rejected 3 times by innovation group, yesterday 17 July 2015 took my car for service and again they send a quote to them but was not accepted while i'm paying them each an every month there's no month that they never received the payments. I really trusted Innovation Group and when i bought the car it was recommended for me but now i doubt i did the right thing to make them my maintenance plan.