Hello. My name is ***** ***** I will be assisting you today.
What router do you have? Can you take a picture of the bottom of the device and attach here?
I'm not sure on billing, I think we'll need secure remote assistance so we can see why serial number is ***** working.
Do you want to continue on?
too blurry I can't see
sometimes serial number will have an extra number or letter at end, maybe try entering it without last 1 or 2 characters.
Anything that says S/N ?
Are you registering it here? https://account.asus.com/product_reg.aspx?lang=en-us&site=us
Checking in to see if you still need help with this issue, if so please reply at your convenience.