on the page "https://www.minecraft.net/en-us/msaprofile/redeem-code?token=XXXXX-XXXXX-XXXXX-XXXXX-XXXXX" (replace the X's with a valid code. link only shows up with a valid code, not a dummy one OR already redeemed code. I submitted a MC experience code) there is a dead link, which is displayed as "Go to Minecraft, Minecraft Preview". (see 'screenshot 1')

it leads to "https://www.microsoft.com/library/errorpages/smarterror.aspx?correlationId=PnKWjgcnwUCzeflT.0.2" which displays:
We are sorry, the page you requested cannot be found.

The URL may be misspelled or the page you're looking for is no longer available. (see 'screenshot 2')