Highly irate potential client

My Fiancè signed up for a contract and the agent **** to her about the amount.

Even though it was higher than expected she still wished to continue if the debit date was changed but for the past three months she has been told the issue is being escalates and still gets invoices every month.

How can they send an invoice and not contact the client.

She has also tried many times to get through to their contact centre with no success at all.