Somehow, a device lock password got set...either by you or someone else, but a human was definitely involved. Unfortunately, there is no way to bypass it. Only the created password can unlock it. There is no "master" or "override" password to bypass it. If you truly cannot figure out who created this password on your BB, then your only option is to fail 10 times, resulting in a complete WIPE of your BB, and you start over. Hopefully, you've been taking regular backups and/or using a Desktop Organizer (e.g., Outlook) as your master data source so that you can recover more easily.
Occam's Razor nearly always applies when troubleshooting technology issues!
New to the Community? Click here and also here for helpful guidance. Also please click here for additional helpful information to guide you as you proceed. I always recommend that you treat your BlackBerry like any other computing device, including using a regular backup schedule...click here for an article with instructions. If anyone has been helpful to you, please show your appreciation by clicking the button. Need a reference to BB10 OS/SR versions? Click here. Need a specific BB10 AutoLoader? Send me a private message.