MangoH red reflashing

I have removed tools app from the MangoH red and when i reflashed the device with fdt2 WP76xx_Release16_ATT.spk, I could successfully reflash but when i view the apps, I could not see the tools app in app list. I have tried this multiple times but no luck. I have also tried switching ON/OFF the switch 7 but there is no success. How can i force reset the device to have the initial state? Tools_Project_Removed.docx (332.5 KB)

You need to go back to some old fw first and then upgrade to latest one

Thank you for your response. Where can i find the old f/w. The following link does not show any archived files for the old fws.

you need to search in source.sierrawireless.com

e.g.
https://source.sierrawireless.com/resources/airprime/software/wp76xx/wp76xx-firmware-release-9/