When writing a blocked term, the user gets this message:
"Your message wasn't posted due to conflicts with the channel's moderation settings."

When writing a long message, the user wouldn't be able to know which one of the words is blocked on the channel. And taking time to find out which word is blocked, and reformulating would be too complex.

The error message should print out the banned word(s) if the user entered one or more banned words, such as:
"Your message wasn't posted due to your usage of the following blocked term(s): ....."