Here is how I bypassed the App Lock and gained access to all of the apps and delete the App Lock app.
Using a Motorola Moto G5 Plus
Android 7.0 (I don't think this is a vulnerability in prior versions)
1) Installed the app.
2) Set the app to give accessibility access.
3) Set my passcode.
NOTE: Went back to my settings and I gave the app device administration privileges as an added level of security.
4) Set the app lock to hide both the Settings screen and the Google Play screen.
5) Tap and hold the app to bring up the uninstall option.
6) Dragged the app to the uninstall trash bin.
7) Tap and hold the square icon (overview button, task switcher) to put my phone into split screen mode (available in Nougat).
8) Tap the overview button now in split screen mode to exit back to the default screen.
9) Tap and hold the App Lock icon and drag it back to the uninstall trash bin again.
10) Now, the option to uninstall appears in a split screen.
11) Tap 'OK' to uninstall.
NOTE: Had I just followed your install instructions in the app it would be uninstalled and all options available. However, I also gave it device administrator privileges (this step I think is only found on your website) as an attempted added layer of security.
12) Tap on "Manage Device Administrators" in split screen mode.
13) Tap on checkbox to remove Norton App Lock from administrator.
14) Repeat process above and delete the app.