Read the forum guidelines
Paid over $400 for modem now told out of date and wants to send a new modem...as I can see I'm not the only person having wifi issues now they want to send me a new modem and after paying over $400 for the old one, they want to charge me another $120 if I trash it!!
What's the make and model of your $400 modem? What data plan do you have?
trade it for the new one!!