Welcome to the community!
I would love to help and see what happened on your modem/router. Can you provide more details on what is happening on the modem/router? If the modem/router is faulty and it still under warranty I can have it replace.
I tried to use your community details to pull up your account unfortunately no match. I'd like to get your account details (Username/Customer ID or Mobile number on file) in case you need a reference.
I will wait for your response. Cheers!