Poor customer service by FNB

I purchased a R500.00 of prepaid electricity and received a token that keeps on rejecting when trying to load it.i have since been trying to contact eskom after been advised to do so .Eskom never answers their phones.i notified fnb and they are still referring me back to them.i am unhappy with the service received and I just want to be reimbursed for this money I have lost and FNB is failing to take accountability since I notified then from the first day.