Bank card randomly cancelled without my knowledge, with zero empathy or proper assistance

Today I decided to go shopping and to my surprise my bank card has been cancelled without my knowledge. Called your call centre and dealt with a very care free tired unhelpful consultant who just casually said its cancelled, he doesn't know why, and there's nothing he can do. Please can this be resolved urgently as I am now in a queue at your bank branch in the Atrium with a consultant having helped me order a new card but at my expense. Which I can't quite understand why.