Not sure what you mean by reset. I am not a technician but just because it works for me after a suggestion by my cable company, try this.
* Turn OFF the power to cable modem and wifi router.
* Disconnect the power connection to each item.
* Disconnect the cable modem line input and output connections.
* Reconnect everything and restart.
I usually wait about a minute before reconnecting.

Please do not flame me if it this does not work for you. Your equipment probably is not the me as mine.
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