Message With Emoji Not Inserted In Reply Messages

I’m having a problem when users reply to a message and include an emoji character from a smartphone. The message is not inserted but the message sent success message and email are triggered. This is only when replying to an existing message. The messages with emoji are inserting fine on new messages. I dumped the content variable and it looks fine but I can’t figure out why the insert is failing. Any help would be greatly appreciated.

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