Hi Wyogold, transfers have been iffy since the IT integration between SPG and Marriott, but anecdotally they seem to have gotten better recently. There are still some reports of missing miles, so you are not alone. I have been caught out earlier this year too, but it was resolved after about two months. It was a painful process with Marriott/Bonvoy refusing to investigate until the six weeks in the T&Cs are over.

More information at this thread: https://www.flyertalk.com/forum/marr...fer-times.html

It appears that any airline or any number of transferred miles may be affected, i.e. factors are random. You've just been unlucky. All the best in resolving this.