When this happens, the setup for comment has switched back to default at the client pc after the update. To solve this problem, please follow the steps below:
Open UBS.
Go to Housekeeping and select Upgrade data files.
Click on Advanced Setting.
Un-tick Use Memo Field as comment.
If it is already unticked in the memo field as a comment, try to tick it and see if the comment appears.
By default, comment notes have no lines. When you untick Use Memo Field as Comment, lines will appear while updating the comments, but these lines will not appear on the printed document.