SHELL MULBARTON ***** fuel numbers

I'm so ashamed and disapointed by what I have experienced at Shell Mulbarton Service centre, based in cnr True North and Saron Rd, Johannesburg. I use Discovery rewards card, which is only accredited to BP and SHELL. I'm used to only pouring fuel on the two fuels station unless I can't find them closer where I'm at. I poured fuel for R300 and while my remaining kms on the clock where 45km, the R300 only gave us 150kms including the 45kms remaining. When we complained(was with my partner) they called the manager, who came and told us that, it is normal and he's used to such complains. He then suggested to reset the car by removing the terminal on the battery. We refused and they shook the car as alternative and nothing changed. We then suggested that we put an extra R100 on the car to check if it might go to where it should. Funny enough nothing major took effect( saying this, as we are used to pouring at Shell Comaro and whe we poured R300 with 30kms range left on the car, it gave us 280km range. In this case it gave 150km range. we have taken pictures and can even go as far as to prove it) even at any fuel station we would get such a ridiculous numbers. We are all experiencing a pich of economy, but I feel cheated by the whole situation and feel ******.

Please assist in fixing this.

Hope this gets to the right people.

Regards

M E Malatsi