What is the ruling on a husband working in the sale and maintenance of ATM machines for banks, and what is the stance of the wife and children regarding this income if there is a suspicion of unlawfulness, and the husband does not accept leaving the job?

The basic principle is the permissibility of selling and maintaining machines used for lawful services. However, it is not permissible to sell or maintain them for those who will use them to assist in forbidden acts, such as a usurious bank; this is based on the Almighty's saying: "And do not cooperate in sin and aggression." It is permissible to sell and maintain them for Islamic banks. As for the wife, she has the right to demand her husband provide for her from lawful earnings, and if he does not comply, she may take the matter to a judge.