Declined foreign transaction

Every month I keep getting multiple “declined foreign transaction” payments that go off at R8.00 a pop. I don’t know what it’s for or how to stop it and it is costing me, this month already it has happened 14 times!!! And no one can help me. What is this and how do I stop it. Last month over 20 times. Disgraceful service and just useless. Really considering after 40 years changing banks.