Found this while looking for some good deals. Here are the terms:
Cashback is ineligible when using codes not listed on Cashrewards.
Cashback is ineligible on orders made via the UNIQLO app.
Cashback is ineligible onAIRism face masks, and Roger Federer RF caps.
Any purchase returned, exchanged or cancelled partially or in full (in-store or online) is ineligible for cashback.
You must return and click through from Cashrewards to UNIQLO every time you make a new transaction/purchase.
Well of course there is no cashback on the RF caps. How else can they afford to pay him $300 Million?