The double opt in bypass setting allows you to control at a master country level the opt in status of new contacts that are added to your MOBIT account. If you are in the US, it is advised that you do not enable double opt in bypass, as you should be following a double opt in process to obtain permission from all contacts that you would like to market to. 

When double opt in bypass is set to YES, any new contacts are created as subscribers.

When double opt in bypass is set to NO, any new contact will be added with a non marketable opt in status.

To access your double opt in bypass settings, head to your settings section, then go to SMS settings. Upon clicking YES, you will be asked to send yourself a verification message.