As Carl said you need to go to
https://www.tredittire.com/product-warranty/
there you need to fill out warranty form and send pictures, you will also need proof of purchase to show you are original owner.
They are pretty good at getting your replacement sent out. I've had two of my rims replaced 1st one came within a couple days, second one took a little longer because of staffing issues that was this last summer. but finally got new rim. even with the issues they are very good to deal with.