Emojicons in ofOffline table shows as?


I am facing an issue in offline storing and relaying of emoticons. The emojicons got ??? instead of the actual code.

I have tried all possible solutions of changing Character encoding from utf-8 to utf8mb4 plus all others suggested in the posts.

This is my stanza in ofOffline table:

{“message”:"???","timestamp ":1443859633023,“senderName”:“John”}814935df-4fa4-453a-885b-ca7e8 7e3be05

Please suggest a possible solution,Thanks in advance.