This might help in answering any questions you might have on Mystic Messenger...
Also please refer to this post for further information on where to file a report to Cheritz.
Please do keep in mind if you have emailed Cheritz do not file a report or vice versa, in short don't email and report all at the same time, just once is enough.
So if you know someone who is posting videos, please do let them know this important information!
So there you have it!
I'm sorry I am not able to help any further, if you are banned from the game you can try to report it either through the email or the web site.
Where do I get the email or web site?? Please refer to the link above!
1.4.4v Now Available
THE BAN MIGHT BE LIFTED FOR EVERYONE, EVEN THOSE WHO ABUSED THE GAME!! OF COURSE THEIR IS A CATCH! SO HOPE THIS DOES COME TRUE!
"Updates on lifting ban for innocent users.
We deeply apologize for the inconvenience caused. With this new update, users wrongfully banned will be lifted and the hourglasses will be added based on the time you could not play the game as a compensation.For iOS update, we’ve requested Apple to approve the new version as soon as possible. We thank you for your patience.
Since it is the first time applying the banning system to the game, we have decided to lift the ban for all users within 7 days after the update of v1.4.4.As a penalty of abusing, the current game progress/hourglasses/hearts of the abusers will be reseted and the abuse records may affect your future customer service. The purchased item(ex.call card)will not be affected.If the account gets banned for the second time due to an abuse, there will be no second lift."
CREDIT FOR THIS AWESOME INFORMATION GOES TO SHIN9095!!
SO PLEASE REMEMBER TO SAY THANK YOU!