I had a similar experience trying to renew my support late last year. I contacted my dealer, and they took care of everything. Except every time I checked my products page, the M40 support was still expired. After a few weeks of that, I contacted my dealer, who forwarded me the string of emails showing that my coverage should be current.
I reached out to a contact I have at Avid, who was great about looking into it for me. Turns out, the avid employee who works with my dealer had done his/her job, but the person who was responsible for actually processing the renewal just... didn't... I guess.
I've never been able to understand why the S6 support cannot be renewed online like everything else. I'm sure there are reasons, but are they good reasons?