Deuteronomy 18 22
When a prophet speaks in the Lord's name and what he says doesn't happen or come true, then that is a not a message from the Lord. The prophet has spoken with contempt for the Lord. Don't be intimidated by him.
Compare with other 3 random translations
KJV Deuteronomy 18:22when a prophet speaketh in the name of the Lord, if the thing follow not, nor come to pass, that is the thing which the Lord hath not spoken, but the prophet hath spoken it presumptuously: thou shalt not be afraid of him.
NIV Deuteronomy 18:22If what a prophet proclaims in the name of the Lord does not take place or come true, that is a message the Lord has not spoken. That prophet has spoken presumptuously, so do not be alarmed.
NCV Deuteronomy 18:22If what a prophet says in the name of the Lord does not happen, it is not the Lord’s message. That prophet was speaking his own ideas. Don’t be afraid of him.