Mercedes Sclass long wheelbase NCT

I have owned this car for over 5 years. Nct until January 2027 Car starts second turn of the key. Suspension lowers after being parked for 3 days or more.suspect drivers front strut.(Have one to go with the car) S320 cdi long wheelbase In my ownership I have replaced - Two struts Both front and rear battery Both front wishbones Both rear control arms Front and rear brake pads Timing chain and guides replaced may last year. Injector seals,injector O rings All injector leak off pipes Two front abs sensors Interior blower motor Screen wash motor Both Front wipers Serviced annually Just had 4 new tyres fitted. Receipts for all of the above present with NCT certs every year in my name too. Located in oldcastle co meath