I don't know how to review a listener

You click on their name/icon at the top and then you can review them

Alternatively, you can click on the yellow star at the bottom of the window near the send button. That also allows you to review a listener.

@Gr8ful22as others have answered, after you open your conversation window with them, under send button you will be able to see a yellow start button. This button is available only after a specific number of messages has been exchanged in conversation (about 30). You can click it and give them star review, but also leave a written review. We appreciate written reviews very much and each is approved before being posted on listener profile. This is important because it gives some space to take appropriate measures after someone gets a negative review, to help listener improve in particular area.

If not enough messages has been exchanged and you are unable to leave a star/written review, and you had negative experience, it is perfectly fine to block a listener by clicking on red block button and fill in the box that appears with explanation. This acts as report, and similar to written review, is really important because it gives us space to work to improve listener quality and take appropriate measures to encourage listeners to improve.