Credit card *****

My mom is a pensioner, 74 years old. Last year Nov she cancelled her credit card with Absa and reported ********** transactions in her account, all of which took place overseas. She also reported a phone call she received from a gentleman with an Indian accent who said he was from Absa and that they were just going a security check. He proceeded to ask my mom some questions which were confirmed by SMS. My mom is very trusting and not fami**** with technology, thus proceeded to co operate with the gentleman as it seemed legit from the sms's. Subsequently she has been in constant contact with Absa, filled out the declaration, and a new can was issued to her. She HSS never been overseas , hardly uses her card and always pays on time. She had been a client of Absa since Volkskas. Today her claim was repudiated. Absolutely shocking! She is in a state of shock and I am fearing for her health! How is this possuble?