Relentless Foschini Spam Calls

My mother has received relentless spam calls from the Foschini group. 10 - 15 calls a day, starting early in the morning and running till 10pm at night. I have contacted you on her behalf and was advised she would be removed from your database, however the calls persists. She contacted you again and was advised she would be removed, however it is still persisting. We have even blocked the number, however the calls persists. This is driving her to the brink of insanity....please make it stop!!! Also, when she does answer the calls, there is no one on the line.