What is the ruling on someone who vowed to fast for two consecutive months, but failed to do so?
He is obliged to fulfill his vow by fasting for two consecutive months, but if he fails to do so then, it remains a debt on him until he either fulfills his vow, or dies. In case of his death, his guardian is supposed to fast on his behalf, or donate food from his estate in return for fasting, but if the guardian fails to do so then, it is all in the Hands of Allah.
Is permissible to buy/sell with non-Muslim?
Yes buying/selling for a Muslim with non-Muslim is permissible as regards what is lawful.
Is the woman who do breastfeeding permitted to break the fast during Ramadan?
It is permissible for pregnant and breastfeeding women to break their fast during Ramadan if they fear harm to themselves or their child. However, they must make up for the missed fasts. If the fast is broken out of concern for the fetus or the baby, expiation (Fidya) is also required along with making up the missed fasts. The expiation involves feeding one needy person with an amount equivalent to a Mudd of food (approximately 600 grams of wheat or rice) for each day of missed fasts. If the fast is broken out of concern for the woman's own health, only making up missed fasts is obligatory. And Allah Knows Best.
I work at a company that provides cash advances of 800 dinars, 1000 dinars, or 1200 dinars, depending on the employee’s years of service. An administrative fee of 40 dinars is deducted from the amount in the first month, and the remaining amount is repaid in installments. What is the ruling on this, knowing that the deducted amount (40 dinars) is fixed?
We fear that the deducted amount may be a means of circumventing interest (Riba). If the deducted amount is equal to or less than the actual administrative expenses, then there is no issue, as some scholars permit the borrower to bear the costs of documenting and managing the loan. However, piety suggests refraining from taking this loan under these conditions, as dealing with private individuals and companies is not the same as dealing with the state, which spends from the public treasury. And Allah Knows Best.