I am using Samsung (S6, Galaxy S6 Edge Plus, Note Edge) device

Step 1:Open your Phone settings and tap on "Battery". If you don't see an option for "Battery" click here

Step 2:Select "Details"

Step 3:Open your App menu and look for "Smart Manager"

Step 4:Select "Battery"

Step 5: Select "Skooly"

Step 6: Under App optimization, select "Turned off for"

Step 7: Press back to save your settings.