Complain

I went to bp garage to get petrol and I used the entrance next to the hostel as usual sadently they are telling me that they can't pour petrol for me because I used a wrong entrance my car is facing a wrong way.i was no my pump is In the write way so can I get petrol no is the answer I got and they kept calling each other to talk to to me .I asked them wen did the rule start and where is it written that that wen u use a certain entrance u won't get petrol. They showed me a small board that I even see. I'm a customer of bp garage and I was so disappointed that I didn't get gas because my car was facing the wrong way.