Wow, glad i found this post, I recently had two stays credited with miles not points, I have been a points earner for over 30 years, this was totally random, I only noticed as the accrual was substantially less than usual.

I have been in contact with Marriott/Bonvoy and they claim that only I can change the preference, which was not the case, waiting to hear back as this was escalated.

I thought my account was hacked.

The irony is that the "miles" were posted to an airline I haven't flown in years, and will never fly again, it is just the ff # had been there forever.

Not sure what happened, any suggestions?