Warning the script will run the next time you start the device
# download script
curl https://gist.githubusercontent.com/Rami-Majdoub/7b5d171989470f4db623e10be47062c1/raw/92ee98501fe130ba86b32096ee59c72d6f0066df/time_reminder.sh > ~/time_reminder.sh
# make script runnable
chmod +x ~/time_reminder.sh
# autostart
printf "[Desktop Entry]
Type=Application
Exec=bash ~/time_reminder.sh
Hidden=false
NoDisplay=false
X-GNOME-Autostart-enabled=true
Name[en_US]=Time reminder
Name=Time reminder
Comment[en_US]=
Comment=" >> ~/.config/autostart/time_reminder.desktop
it works until you suspend the device