Is it permissible for the company to return to me the amount previously deducted from me, in exchange for the excess profits it earned from customers with their consent?

The questioner must fear Allah concerning the company's funds entrusted to him, because the company appointed him as a trustworthy agent. Allah commanded the preservation of trusts and forbade betrayal, and the Messenger, peace and blessings be upon him, said: "All of you are shepherds, and all of you are responsible for your flock."

Therefore, he must act within the bounds of the company's interest, and whatever he earns in its name is its right. As for the amount deducted from his previous salary due to his favoring customers, it is the company's right; because an agent is liable if he sells for less than the price, and the profits exceeding the original price belong to the company, unless the company donates them to him.