I can’t erase all content and settings on my iPod air

My iPod has been turning itself off and showing that it has no charge but it clearly does. I’ve tried to shut it down manually and restart as suggested but does not work so the next suggestion was to factory reset my..

ipod.

when I try to do this and I enter in my correct passcode it says that .. my passcode is not recognised. I’ve tried entering in 3x after resetting and even tried to change my passcode and retry to no avail!

please can someone help