u/Temporary-Mention-32

In March a bought a 2006 Tundra for 7k with supposedly 187,6xx miles. I unfortunately ran the Carfax recently and was devastated to find that the last recorded mileage was 311,433 as of September 25.

Has anyone else had this happen?
Any advice on what to do in this situation?
How worried should I be about future resale or further investment in the vehicle?
Does carfax ever get things wrong?