The router can be reset to factory default settings with a physical button.
Locate the reset button
Look on the back of the TP-Link router. The reset button is typically small and red, but this can vary slightly between models. The button should stand out as the smallest one and is often labeled as a reset button.
Use the reset button
While the router is on, press the reset button and hold it for at least 10 seconds. The SYS LED will flash slower, this is an indication the reset has begun. Let go of the reset button and allow a few minutes for the process to complete.
You can also reset the modem or router using the TP-Link web portal.
Access web portal
To access the web portal, log into your TP-Link router.
Reset to factory default
Look under System Tools for an option called Factory Defaults. Select Restore to initiate the factory reset.
Wait a few moments for the router to restart. When it boots, everything will be restored to factory default settings.