What is the ruling of the Sharia on a man who divorced his older wife in court, identifying her as the younger one, without the younger one's knowledge? And does the divorce apply to both wives simultaneously?

If a husband is confused and divorces his younger wife, thinking she is the older one, the divorce unequivocally applies to the younger wife. As for the older wife, divorce does not apply to her unless she brings her husband to a judge to seek separation. Therefore, divorce applies to the younger wife even if she is unaware of it, whereas divorce applies to the older wife only in the case of judicial proceedings, not through a mere fatwa (definition). In such cases, one must refer to the Sharia (definition) courts.