Thanks Ahmed, does it sound rude, let me refresh your memory. Is there another way of saying? Like, just to recap you?
'Let me / Allow me to refresh your memory' is not rude, but informal. So, you can use it with a friend as you have mentioned in your question. If you want to sound formal, you can use something like 'May I remind you that / of ....?" In addition, if you are talking to a person in charge and you want to repeat the main points of an explanation or description, you can say, "To recap, ....................."