Bad service/*********** personnel/spares unavailab

We send our truck into Volvo for a 9000Hr service and a list of other issues to be repaired, some preventative maintenance issues was requested, after three weeks of the unit being in the workshop, numerous calls from us, promises and commitments from Volvo, the unit was eventually repaired. We had a call from the supplier requesting major work to be released, but upon inspection from my mechanic, it was found that the personnel from the workshop made a basic assessment blunder, which would have cost me north of R20K, when asked why the repairs took so long, we were informed that the they have a problem with getting spares, as a OEM I find it utterly unprofessional on their part, upon loading a customer complaint on their website, I got an automated reply saying a Volvo Truck representative will contact me, this was on the 03rd March 2015<br> This is not the first time our company had bad service from the supplier.