Facebook said it had taken down a post as soon as the company learned of an auction held to seek the largest dowry for a South Sudanese girl from the highest bidder.

The social network reportedly didn’t delete the post until 15 days after it was published and nearly a week after she was already married.

The auction started on Facebook on October 25. Nyalong Ngong Deng, 16, was married on November 3, and Facebook took the post down on November 9, CNN reports.

Facebook told CNN that it had disabled the account of the user who posted the auction on the platform.

"Any form of human trafficking -- whether posts, pages, ads or groups is not allowed on Facebook. We removed the post and permanently disabled the account belonging to the person who posted this to Facebook," a company spokesperson said in a statement.

The girl’s family received 500 cows, three cars and $10,000 in exchange for their daughter. The competition for Nyalong’s hand in marriage was won by businessman Kok Alat after he outshone four other suitors, including a high-ranking government official in South Sudan’s Eastern Lakes State.

Plan International's country director in South Sudan, George Otim, said: "That a girl could be sold for marriage on the world's biggest social networking site in this day and age is beyond belief."

Otim said that offering payments is part of the country's culture, but that in this case it "was taken to another level because of technology."

Article 15 of the South Sudan constitution stipulates that any person of marriageable age has the right to form a family, and Article 17 guarantees women and girls the right to consent to marriage.

Article 17 also defines a child as anyone under the age of 18, and further states that the best interests of the child will be protected in all matters related to his or her life, and that they should not be subjected to exploitative practices or abuse.