Dishonest call centre agents

I referred my husband to sign up for discovery bank. While we were signing up online and downloading the app, a discovery bank consultant called as she had seen the online application. My husband told her that he is fine as he will apply on the app. We wanted to use my referral code on the app. She told him that he can only go onto the app after doing an application with her. This was a lie. Because she tried to get the sale, we could not use the referral code. This level of dishonesty from the call centre is disgusting. How can you trust bank call centre stuff with your money when they are so dishonest.