Bad customer service

Called this morning to check availability of gas to refill my cylinder. Precious confirmed there was. Took cylinder through shortly thereafter-11:30. My cylinder was labelled&taken through with the lady advising it would be about 2hours cos there was a queue. I asked if it would be done before close at 2pm and was told yes&I accepted this. Arrived back just over 2hours later&get told its still a while to go. When I ask Precious if this will be done by 2pm cos that is what I was told she gives me attitude about well she didn't take my cylinder from me&she didn't tell me it would be ready&proceeds to talk to the other lady at the info desk in vernacular about me in my presence. I then get told I must come back tomorrow for it. I made it distinctly clear at drop off that I preferred to have it done today hence my acceptance of the 2hour wait. Your staff have wasted 3hours of my day&I still have an unfilled cylinder that I had to go fetch from your gas area myself after having to wait when I could've gone elsewhere. Absolutely disgusted by the behavior&attitude of Precious-you need to educate her about what customer service is. &teach your staff to not make promises they can't keep.