My finger print is not showing up on my Samsung S5 screen and I forget my alternative password, how can I reset my alternative password?

[AC Question]

my finger print is not showing up on my samsung s5 screen and i forget my alternative password

I used my phone my phone this morning with the fingerprint option and I don't know what went wrong now it is just giving me the alternative password option and I don't remember it. How do I reset my alternative password?