WPS (
Wi-Fi Protected Setup) is a facility provided by modern wireless routers to make is easy to connect wireless devices such as printers. Unfortunately,
WPS is not very secure and it can be subverted in order to gain access to routers that are in theory protected by strong encryption.
From what you have already told us, it appears that your wireless router has been hacked by someone who has either guessed the password or has defeated a weak encryption protocol such as WEP, or maybe even WPS. You should certainly be using WPA2-PSK (AES) encryption as
ukhardy07 has advised and it would probably also be a good idea to disable WPS if your router supports it. Of course, you could just do nothing and wait to be hacked again.
Edited by micksharpe (Fri 24-Jun-16 23:00:51)