FNB Home Loan No one calls me back

My husband and I have a home loan with FNB. We have a linked savings account to the home loan. I wanted them to take the money in the savings account and pay off the home loan amount. They kept telling me to complete the document That document stated that it is reducing my monthly debit order I kept asking them that someone from Home loans can give me a call as I live in Zambia and only come home once a year. I completed the document although it did not seem correct Now my savings money is gone My debit order have been decreased and I cannot get hold of anyone to phone me. This is so bad My husband and I are thinking of flying down to go see a Senior person from Home Loans at FBN Head Office.