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Does anyone else have common physical access to your Toshiba laptop?
If so, I'm sorry to have to say that someone with such physical access has probably booted up your computer in your absence, and activated the BIOS password.
(- Unless, you might have done so yourself, last bootup?)
I have never thought about it this way before, but such an act might be interpreted as criminal grand theft, or an attempt thereof, or conversion larceny grand. (I admit I'm not legally learned, but if that's what has happened, it does count as some sort of crime committed.)
Such BIOS lockout is meant for owners of laptops to secure their machines. It is also, over decades, a facility that has been developed to thwart theft, and is thus developed to the point of being nearly unbeatable.
If you did not set it yourself, and if you cannot guess the password (trying isn't forbidden at all... you can try multiple times usually, if not always...), then you have an unfortunate situation to say the least, and I'm sorry.