What kind of phone do you have?
Do you mean Safe Mode?
If in Safe Mode generally a restart is all that is needed to revert back to standard mode.... If not able to do regular reboot, hold the power button down until device powers off, then turn back on.
Getting your phone up and running is a must. lukevinyl asked great clarifying questions. What do you mean by Smart mode? Are you seeing a particular message on your screen that prevents you from restarting the phone?
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