[Ali Imran]

Again many English translations will say
Someone replaced Jesus on the cross.

Sahih International
And [for] their saying, "Indeed, we have killed the Messiah, Jesus, the son of Mary, the messenger of Allah ." And they did not kill him, nor did they crucify him; but [another] was made to resemble him to them. And indeed, those who differ over it are in doubt about it. They have no knowledge of it except the following of assumption. And they did not kill him, for certain.

So, the answer to my question, "Who told you that?" is a man. Allah didn't say that.