web monitoring does not fire alert

[umer]

I have followed steps in the documentation to setup web monitoring
I can see that the trigger fires, but the alert is not fired

here is my trigger rule ...
{some-host:web.test.fail[some-scenario].avg(600)}>0.5
severity: Average

and here is my action config ..

Maintenance status not in maintenance
Trigger value = PROBLEM
Trigger severity >= Average
Host group = some-host-group

some-host belongs to the some-host-group

[LenR]

Check that the user referenced in the alert has at least read only access to the host.