Be confident. It’s not you, it’s the phone.
Telephone calls can be problematic. You cannot see the person you are talking to, the quality of the line might be really bad, they might be speaking too fast or too quietly. The key is confidence: ask to repeat, as many times as you need. The ultimate goal is mutual comprehension – don’t settle for asking for confirmation via email.
Here are some phrases that will help you on the telephone. In which situations do you think we can use them?