Stelantis service costs

I have a 22 plate 3008 1.2 puretech with approx 40k miles.

I pay a monthly fee for the extended warranty and as a condition I must have the car serviced with Peugeot.

Just called to book in my service which is due in April... Over £500! When I asked what was included it was nothing unusual apart from the cabin filter and replacing spark plugs. Lots of checks however.

The infamous belt was swapped out with a full engine stripdown at the last service.

I'm not sure how to proceed with this? It seems extremely excessive to me.