Hey @Rfares,
I'm sad to see you're having trouble with this service. Did you purchase the device directly from us? If not, can you make sure you have the proper MMS settings saved in your phone? You can check them out here under ``How to configure an Android device``.
Also, can you confirm if your mobile data is on?
Though using MMS doesn't deduct from your data bucket in your plan, it does require your mobile data to be on for this service to work.
Let us know! 
