* Have you tried connecting your laptop to a different network? Is it working properly? or tried using another laptop to the network? (for isolation)
* After upgrading the router's firmware, have you tried resetting it afterward?
- If you haven't reset the router, you may try it first. I recommend to reset it by pushing the reset button on the router for 30 secs, then unplug/replug the router. Try to reconnect to the router with its default settings, if it works then try to return the previous settings.
NOTE: Resetting the router will set the router to default settings. (except the firmware)
Thanks
DrScott