CANCELLATION OF CONTRACTS

We have cancelled and settled our contracts in June 2015 already. We paid more than the amounts given. We were given an amount via e-mail together with a note that said that there will be one more invoice for each line at the end of June which we will be liable for. We did receive that invoices (which are correct according to me) and before we could pay same the consultants started phoning us giving us enormous amounts that are outstanding. Ever since we are trying to resolve the matter but apparently the consultants are not trained well enough to sort this little problem out. Every one has another story and will get back but never do. we also do not get any respond via e-mail.