Is it Islamically permissible to engage in the business of mobile phone recharge cards, where capital is invested and stipulated to be left for days, with the acquisition of exaggerated profits that may reach 2000-3000 EGP per month for every 10,000 EGP, or even 6000-7000 EGP per month, without often receiving the cards themselves?

Trading in mobile phone recharge cards is, in principle, permissible. However, setting a specific profit margin on the capital invalidates the mudarabah (profit-sharing partnership) and turns it into a forbidden usurious loan. Similarly, stipulating that the money remains for two or three days is an unlawful condition, as it constitutes a loan that draws a benefit. Paying and receiving money is permissible if the transaction is free from the aforementioned violations, as it is assumed that these funds are for mudarabah in the cards. Caution must be exercised regarding the fraud, deception, and exploitation of the vulnerable that occur in this trade.