First request the permissions and make sure the permissions have been granted before starting the service... see again the example project...
The Locationservice.LocationChanged event will fire only if your app is up and running. If your app is in the background, no user interface changes are possible. You have to setup the web background functionality as described in the example project... there is a MySql example and an example to send an email via IFTTT.. .
It does not look like you read the documentation or tried the example app...
Taifun