Bank card issues

I had Uber debit my account on the 29th. Called the branch on the same day at 15:29. Was on the call for 13 m 8 sec with a lady by the name of Ayanda she helped alot with answering my questions and found no fault with her. On Tuesday the 2nd I tried to use my bank card and it declined 3 times.. later wanted to pour petrol it declined again!!!. Yesterday the 3rd I called in and I was told my card is blocked, for what?? They couldn't tell me.. I was then told I need to visit the branch for a new card.. Njanii????