Default [Q] Restore Converted HTC One (GPE) to factory ROM

Need help!! I have successfully converted my HTC One to GPE last week, but I want to restore it to its original factory ROM, the one with HTC Sense so I can recover its warranty for repairs. But when I tried to flash it with RUU it got stock on bootloader with *** TAMPERED ***, *** RELOCKED ***, *** Security Warning ***, how ca I fix this? T_T