I tested your bot, and "Hello" gave the response "Hey there, what's up?"
My guess is that you or another user flagged responses as offensive while chatting (red flag button). Flagging a response will give a profanity error if used.
You can clear your flagged phrases from your bot's Admin Console, in the Training & Chat Logs page. Select "flagged response" for "all time" and clear any that should not be flagged. You had a bunch of phrases in there, so I cleared them.