How do you return a faulty apple charging cable under warranty?

I have had a charging cable for about three months now, and it starting malfunctioning about a month ago. It choses to charge and then stop charging whenever it wants to which is frustrating because it takes two times longer to charge my phone. I want to replace it and I believe its under warranty, how would I do that? I see it in my order history but I'm not sure how to return it over mail because of the coronavirus. Thank you for any help you can give!