There are three cases for the purchase process: the first: in cash, and in this case, the amount is directly deducted from my salary at the end of each month, without any additions; the second: if I wish to pay in installments, the bank sends a direct message for each purchase, and I respond to the message that I want to pay in installments for three months as an example, and thus the bank takes a profit margin of two percent; the third: when buying gasoline, an additional twenty piastres is always added to the total amount of the gasoline price. What is the ruling on dealing with this card?