Originally Posted by
somekindahate
If you have both a Marriott Rewards and SPG account, you need to login using your actual SPG number and password. Make sure you are logging into the SPG version of the site (or just visit starwoodhotels.com). If the SPG Number/password isn't working, you may need to reset your password providing your SPG number
https://www.marriott.com/forgotPassw...mi?program=spg
When you login with the old SPG Number, you will get a message stating your new number. Both numbers, new and legacy, will be visible on your Profile page.
Unfortunately, that link kept taking me to a place where I could reset the password on the Marriott side, not the SPG side (yes, even with the "...program=spg" command). Evidently, some issue with browser history/cookies/whatever.
Late yesterday, I got an e-mail from SPG about something unrelated (must have been really important news, I already forgot the topic) that had the new SPG number on it. I cleared everything from the browser, opened a private window, and logged in with the new number. Everything worked fine and I was able to merge accounts with no further issues.