Bad Communication with Discovery Life

All I want to do is change my bank details. They sent me a form to complete. I completed it. They then told me to complete another section but the section didn't apply to me so I asked what I should complete. I followed up as there was no reply only to be told my bank details are the same THEY DON'T ANSWER YOUR QUESTIONS FULLY and each time you have to deal with a 24 hour to 72 hour waiting time. It's ridiculous. I feel it's a nightmare dealing with the life insurance department.