There should be a little white reset button on the back. If you press that it for 10 seconds it will reset your router to 'factory default' conditions.
The IP address will be 192.168.1.1 and the username will be and the password will be 1234.
This will allow you to re-setup the device as an access point but be sure to turn off DHCP.
I normally take an Avery label and write the IP address, username and password on it and paste it to the bottom of the device, makes it a bit easier to manage in the future.
link to user manual: »www.winncom.com/pdf/Zyxel_X-550_···uide.pdf--
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