Please follow the steps below to uninstall OneClickMonitor:
1
How to Uninstall OneClickMonitor?

Open "Settings" and then tap on "Security"

Tap on "Phone Administrators"

Uncheck "OCM"

A Popup will appear, click on "Deactivate". A confirmation alert will show, tap on "OK"

Go back to "Settings" and then tap on "Applications"

Tap on "Application Manager" and then look for "OCM" and uninstall it.