What is the ruling on working as a medical sales representative for a pharmaceutical company that requires selling a certain quantity of medicine, given that some resort to "burning medicine" (selling it at a reduced price to fictitious warehouses) to achieve profits, knowing that this may affect colleagues, and is it permissible for me to perform this act in the work areas of those who cause me to be deprived of profits?

The sales representative is an agent of the company and may not act except as authorized by it. Burning medicines is impermissible because it relies on fictitious invoices or the sale of free samples. What was taken from the company with invoices must be returned, as must what was sold from the free samples. What remains of them must be returned to the company unless the company permits otherwise, along with repentance. It is not permissible for the representative to sell within another's territory due to the harm involved, as the Prophet, peace and blessings be upon him, said: "There should be no harm nor reciprocating harm."