Is it obligatory to renew the intention for making up missed fasts for each of the six consecutive days, or is one intention sufficient for all of them? And what is the ruling for someone who sufficed with one intention?

Formulating the intention (niyyah) at night is a condition for making up missed Ramadan fasts. The intention for fasting must be renewed each night individually. Based on this, a woman fasting six consecutive days with a single intention will only have fulfilled the requirement for the first day. She must make up the remaining five days because her fasting for those days is invalid due to the lack of intention. The matter of intention is simple; whoever thinks of fasting tomorrow, or wakes up for suhoor, has made the intention.