Relativism says truth isn’t absolute but is dependent on the individual, culture, or time period.
A relativist may say, “people once believed the world was flat, but now we all know a different truth, that it is round. Therefore, truth is relative.” However, it was always true that the world was round — our belief about it is what changed. Beliefs can change, especially as we acquire more knowledge about reality. Truth (and reality itself) does not change.
A relativist might argue that “I am cold” is a relative statement. It only applies to me. It is my truth. But it’s true for everyone that I feel cold at that moment, even if no one else feels cold.