The following issue has been confirmed:

After today’s maintenance, the Friend-Specific Lucky Mirrors for Sanae Kochiya (F1.-5), Reimu Hakurei (1;4), Marisa Kirisame (D8.-5), and Yukari Yakumo (L50ws) could not be used.

This has now been fixed.

We sincerely apologize for any inconvenience this may have caused.