I type the correct lock screen password but my screen would not open up?

[Android Central Question]

I use Samsung S7 edge. I have set up a password and fingerprint for my lock screen. I changed my password to a new one and it was working fine for a couple of days but yesterday when I typed it the screen wouldn't open up even though i know 100% that the password I type is correct. I open it up with my fingerprint. But once I turn off my phone I would have to type the password and then it won't open up. What to do? I have to update my phone but couldn't due to the password issue.