After that I knew I had done sth wrong

The phone rang.
I picked it up, hopeful.
The caller spoke, "Good afternoon. Do you want your money to be safe? Go to our bank. Here you can get up to 4% interest for the first five years!"
"I'm not interested." I hung up with an annoyed groan.
The phone rang again.
I hung up without looking at the number. What else did this annoying bank employee want from me?
It rang again.
I hung up the phone. But then I caught a glimpse of the phone number.
Sofie.
I called her.
The number was occupied.