Is a second marriage contract accepted and validated before the family, knowing that there was a first marriage contract three years ago without the family's knowledge? And what is the Sunnah regarding this?

The original ruling is that a marriage contract is not valid except with the presence of the woman's guardian and two witnesses. If a Sharia judge oversees the contract or rules it valid, then it is sound and cannot be annulled. Repeating the contract after its validity is pointless, and the first contract is considered the valid one. The second contract is void due to its lack of benefit. If the court accepts performing the contract a second time, there is no harm in it, but it is considered a nullity that does not affect the validity of the first contract or any conditions stipulated therein.