Hi,
According to the [https://www.beltronics.eu/doc/09500ixOwnersManual.pdf|owner manual] here’s how to reset the unit back to its’ factory default settings:
“Restoring the Factory Default Settings
To restore your PASSPORT to its original factory settings, press and hold the “SEN” and “BRT” buttons while turning the power on. A Reset message will be displayed, accompanied by an audible alert, acknowledging the reset”.