Note: If you choose factory reset, you will return the phone to the original factory settings and will erase all current settings, including the directory and call logs.
On the SPA itself, press “Setup” (https://www.cisco.com/c/dam/en/us/support/docs/collaboration-endpoints/spa901-1-line-ip-phone/108802-5220-001.png).
Go to Factory Reset (14) using “Navigation” (https://www.cisco.com/c/dam/en/us/support/docs/collaboration-endpoints/spa901-1-line-ip-phone/108802-5220-003.png).
Press the “OK” soft key. SPA will reboot and will be back to its default settings.