What loopholes in the Thirteenth Amendment were the Fourteenth and Fithteenth Amendments designed to close?

The Thirteenth Amendment abolished slavery and made it illegal to own slaves in any context. However, while people who were slaves before were free men and women now, they did not have all the human rights, and could therefore easily be discriminated, discriminated, abused and institutionalized denied of the rights.

That is why the Fourteenth and Fifteenth Amendments had to be ratified.

The Fourteenth Amendment gave ex-slaves their American citizenship, as it claimed that all the people who were born in the United States or who naturalized will be granted full citizenship. This gave African-Americans the same citizenship rights as all other American citizens.

The Fifteenth Amendment's ratification ensured that they shall not be denied the right to vote, as it proclaimed that all the citizens must have this right, despite "race, color, or previous condition of servitude". While there were still people and organizations that tried to find loopholes and deny African-Americans their voting rights, the Fifteenth Amendment was designed exactly to try to prevent this.