I'm sorry about the issue. Did it work previously? Or is this a new printer or new modem/router, etc.?
Can you disconnect the power cord from the modem/router device for a few minutes, then re-connect and check?
What is the brand/model of your Internet/wireless modem/router device?
Do you have windows xp, vista, or 7, or 8, 10, or mac computer?
What happens when you install the printer's driver / software on the computer?
Please reply at the box below. Thank you.