What is the ruling of Islamic law on the validity of the Hajj of someone who went to Hajj with an administrative visa that was given up for a fee, and is this transaction permissible?

If a transportation company for pilgrims deliberately obtains more visas than it needs in order to sell them, then it is impermissible to buy from it if doing so results in depriving others who are more deserving of the visa. However, if the company requests visas according to its needs and then, due to a circumstance, dispenses with some of them, there is no harm in buying them.