Manager at Bp rude and disgusting behaviour !!!!

i am an absolute regular customer and bp garage verulam.. over the weeknd my babys stainless steel flask melted my cheque card.. no serious damage to card.. or chip.. or numbers.. just a side problm.i filled up for 300 rands and bp card machines regularly give problems. my card ddnt work immiediately..hence a lady manager approached and rudely said im making excuses as i dnt have funds. i carmly explained bt she continued embarassing me. i then asked her to re use card and it went thru..she asked the bowzer guys repeatdly the amount as if i was not capable of paying a measely 300 rand. im upset and disgusted and that manager needs to learn customer value. i tip my bowzer boys each time i use bp garage.. so i am very upset at the service i received.. only from the arrogant lady manager !! i am not sure why ethical people are not put in positions like these...