Something that is probably related:
With https scanning disabled, the logs contain a single "Connect" entry for each https session.
I have determined that the Size information on the log entry represents the total volume of traffic moved during the session, and that the log entry is not written until the session is closed.
Youtube (and other Google sites) are fully https-based. So the best that we can expect is that the quota will be updated when the session is closed, at which point a new session will not be allowed, but it does not solve your problem with the long session.
Https inspection might solve the problem, because each request is logged separately. That requires deploying the UTM CA and a proxy configuration to each device.
Something that is probably related:
With https scanning disabled, the logs contain a single "Connect" entry for each https session.
I have determined that the Size information on the log entry represents the total volume of traffic moved during the session, and that the log entry is not written until the session is closed.
Youtube (and other Google sites) are fully https-based. So the best that we can expect is that the quota will be updated when the session is closed, at which point a new session will not be allowed, but it does not solve your problem with the long session.
Https inspection might solve the problem, because each request is logged separately. That requires deploying the UTM CA and a proxy configuration to each device.