Unacceptable job from PE Suzuki Service Centre

I took my Suzuki Van in for it's 1st 15k service. I was asked if I would like my van washed. I stated that I would want it washed. When I got the Van back the back had not been vacuumed or cleaned - they had only cleaned the cab. I found this totally unacceptable- why offer a wash and then do such a mediocre job!!!!!