Hi all from a mature newbie

I am slowly getting used to the pi but have hit a couple of issues head on, I am using a powered usb hub and when I add a wifi dongle to either the hub or the pi itself I connect without any issues to my router, however after a short time I lose the connection and cant get it back until I reboot when it connects again. All the equipment I am using has been purchased from the pi store so should be ok.
Hoping for help!