Alpha numeric passcode
i changed my passcode to an alpha-numeric passcode using only letters. when i locked my phone it didn't come up the keyboard but the numbers for like a 6 digit code. i tried my old passcode and i tried the new one but nothing is working. i don't understand and I'm scared my phone becomes disabled.i tried to connect it to my laptop but it says i need to unlock my iPhone before it can connect to iTunes?! Please help.
iPhone 6s, iOS 10.1