Overcharged and can't get hold off anyone to solve it

Ordered a car through a third party. Confirmed with the counter staff as I was picking up the car that no one way fee will be levied, I got a verbal confirmation. To my surprise when I was invoiced, I was hit with R1350 one way fee, R115 document administration fee which was never explained, R40 refuelling fee although I refuelled the car myself 3km from drop off. Trying to get hold of Europcar to solve this mess has been a mission, been bounced from one call centre to another. I have spent nearly R300 of airtime trying to talk to someone!