One of the weekly "Street Enforcer" missions says it requires 200 wins, but I'm already above that threshold and I still can't claim the rewards.

Same issue here, weekly mission/win 350 fights but unable to complete mission

I think when they got nerfed the text got changed but not the bar to claim the rewards.

I think it's still 250 / 400 in your photos

No, I'm at 267 now and I still can't claim it. Could be even higher of course.

Im upto 400 hits now, still no option to claim. Unlikely to find out if its any higher as there is only a few hours remaining on it 🥲