Sets are not accessible

I started the 89 OVR BND Collector Series set and put one card into it a few days ago. Since then, Sets is completely inaccessible. Selecting the Sets tile kicks me out of MUT with “Our servers cannot process your request at this time.” The same thing happens when I select Add to Sets from an item in my Binder. The Madden Companion App also gives the same error when I try to access Sets. Other MUT functions work normally.