MusicBee cannot retrieve tag from Gracenote from November 28th.
Guessing from Japanese BBS and tweets, tens of Japanese users seem to encounter the same problem.
I tried ripping 20 CDs (which are sold in Japan) by MusicBee ver.3.3.7491 and can reproduce this phenomenon by all.
(Unfortunately, no relevant logs are recorded in Error Log.)
I'm not sure if it's MusicBee's bug or Gracenote's matter, and if it also happens in other regions,
but by iTunes and Quintessential Media Player, I can get tags from the CDs used above.
Any help would be much appreciated.