What is the ruling on an oral marriage if it takes place with the knowledge of the wife's brother and the husband's acceptance?

Marriage is not valid without its pillars, which are: the presence of the woman's guardian (wali) or his representative, two just witnesses, and a formula indicating the contract. It is not permissible for a woman to undertake the marriage contract for herself or for others, even if the guardian is present. What was mentioned does not constitute a valid marriage contract, and the woman is considered a stranger to the man, and their cohabitation is considered zina (unlawful sexual intercourse). If he wishes to marry her, he should propose to her guardian and marry her in a lawful marriage that fulfills all its pillars.