Location request plugin not prompting user to turn location on - cordova-plugins

Question

I'm using the cordova-plugin-request-location-accuracy plugin to prompt the user to turn location on (if not already on). However the prompt doesn't show, and I get the following error
Accuracy request failed: error code=4; error message=User chose not to make required location settings changes.
Here is the part of the code I've called the plugin
function init() {
document.addEventListener("deviceready", watchPosition, false);
}
function watchPosition() {
cordova.plugins.backgroundMode.enable(); // enable backgroundMode
// Check if location settings are turned on. Prompt user if not turned on
function onRequestSuccess(success){
console.log("Successfully requested accuracy: "+success.message);
}
function onRequestFailure(error){
console.error("Accuracy request failed: error code="+error.code+"; error message="+error.message);
if(error.code !== cordova.plugins.locationAccuracy.ERROR_USER_DISAGREED){
if(window.confirm("Failed to automatically set Location Mode to 'High Accuracy'. Would you like to switch to the Location Settings page and do this manually?")){
cordova.plugins.diagnostic.switchToLocationSettings();
}
}
}
cordova.plugins.locationAccuracy.request(onRequestSuccess, onRequestFailure, cordova.plugins.locationAccuracy.REQUEST_PRIORITY_HIGH_ACCURACY);
// start geolocation
checkPeriodically = setInterval(checkTime, 10000);
var watchID = navigator.geolocation.watchPosition(onSuccess, onError, options);
...
The rest of the program runs fine (when the location is manually switched on). What is causing this to fail? Thanks.