missing gear leaver cover

I used these people the other day when I went to the airport. They take your car at the domestic departures and store it somewhere and then bring it back on the day you arrive again washed. I landed late and it was dark and did not notice that the cover on the gearlever was missing. I noticed it the morning after and let them know but their response is one of no help. They just say that they checked and can not find it and that is it. The cover is not something that comes off easily and makes me believe that it was ******. Wil not use them again