Cell phone J4 Core or Plus LOCKED how to solve very easy

J4 core or J4 plus completely locked on the black screen and when pressing the power button it appears only two icons to restart and disconnect.
This is one of the easiest cell defects to solve.
Pressing the power button displays the following message: Touch again to restart your phone. But nothing happens when you touch
This solution also applies in the following situations:
J4 caught on samsung logo
J4 with frozen screen
j4 Does not turn off
J4 caught on black screen
j4 only appears to shut down and restart button