Is a wife obliged to return the dowry to her husband after he learned of her previous marriage and consented to it, and their marital life continued, and then he asked for a separation and demanded the return of the dowry?

The majority of jurists are of the opinion that the defects in a wife that establish the husband's right to annulment are those that prevent intercourse or cause repulsion and infectious diseases. This does not include whether she is a virgin or previously married, or the number of her marriages.

Thus, your husband has no option or right to demand the mahr (dowry). Rather, the husband's consummation of the marriage after his knowledge and acceptance of the condition forfeits his right to seek annulment or the return of the mahr.

If the husband wishes to divorce or has already divorced, he must pay the wife her full mahr.

The wife can resort to the Sharia court to resolve the matter.