I'm having this issue when adding certificates in a subclass in the JSunrise revision, through the mod that is available here on the forum.
I have these protections and I believe it is blocking the certificate mod in sub classes, someone recommends a counterstart.
INI:
# Check players for non-allowed skills
# Default: False
SkillCheckEnable = True
# If true, remove invalid skills from player and database.
# Report only, if false.
# Default: False
SkillCheckRemove = True
# Check also GM characters (only if SkillCheckEnable = True)
# Default: True
SkillCheckGM = True