Weird iPhone 7 security issue

Good day Apple. One morning, I was going to unlock my iPhone 7. As usual, it asked me for touch ID and I configured it to automatically go to the home screen after touch ID verification. But after doing so, it said that it was unlocked and the lock icon went away. So I pressed the home button and then it asked for my password to unlock for no reason! Can anyone help me with this issue?

From ShOddY.