can not access recovery on htc one m8
If your volume down button isn't broken, may be the "fast boot" feature is activated in the settings (not to be confused with fastboot) that can prevent the phone from booting in the HBoot. 
Try this: 


From the lock screen, press the power button 
Then select reboot or restart. The phone will reboot
Hold volume down button before the phone power itself on.
You should be in the HBoot Menu (3 android guys)
From the just select Clear data


Hope this helps you.