As suggested, did you restart the modem?
If issue continues, try resetting it. You can reset it to its factory settings by holding down the reset button on the back of the device for ten (10) seconds.
Try a ethernet (hardwired) connection to the modem to see if you can connect.
If problem persists, you can chat with Fizz support.
The idea of this page https://fizz.ca/en/contact-us is to explain how you can access the chat bubble. If you do a search in the Solution Hub related to your issue and access the help page the chat bubble will appear at the right corner.
If the chat bubble does not appear, this means that the number of sessions waiting for our answers surpasses our processing capacity. If that happens, send us a private message via Facebook Messenger or Twitter.
In order to help the Fizz community evolve with your question, do not forget to identify the best answer given to you by members of this discussion group using the Make Best Answer button.