Comment Types (Official Note Types) are tied to School Levels. If the user is enrolled in a School Level that is not enabled in y our Comment Types, they cannot be pulled into the recipient field. 

To enable grade levels in your Comment Types, a Comments Manager can:
  1. Navigate to onRecord.
  2. Select Settings > Comments.
  3. Under the Comment Types tab, click Edit to the right of your Comment Type.
  4. Select the Grade levels, per school level, that you want to use this Comment Type with.
  5. Save & Exit.
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