Ucount card not accepted, made me late for work

Good morning. I went to your Caltex in Woolwash road Amalinda, East London to get fuel on my way to work. I check three times with the petrol attendant and his supervisor as to whether I can use my Standard Bank Ucount card to pay for fuel. They said yes no problem. The speedpoint didn't say no funds or anything like that, the error code returned was "authorisation declined". I showed your attendants the confirmation smses of my account balances and pincode. They maintained that you do accept Ucount card and even tried a different speedpoint. Please help so that I can pay. I had tried to call the owner Mrs Pape however she did not answer her phone.