Time limited users not disconnected

[Dogmor]

Hello,

I have created user with time limit of 1h and 2h. Sometimes a 1h user connect but at the end of time, he is not disconnect automatically and he can continue to work until i disconnect him manually. But he cannot login again because time is over. This issue happen randomly and can touch about 5% of all users.

I want to know if i can create a cronjob which trigger every 15 minutes for example and just check the online users and verify if they have time left otherwise the cronjob will disconnect them automatically. 

Thanks