bad service

We ordered online and received invoice for it. Then after we paid via e.f.t. we receive a email stating we must pay a extra R35.00 for courier charges. On the original order \as stated on online platform"we dont pay courier charges as our order exceeds minimum requirement. The lady named Monja just rep**** via email that \""they cant absorb everyone's courier charges. The courier company says we are a rural area. St Helena Bay. But the previous 3 times we ordered the same way no charges"