Legal Question in Real Estate Law in Illinois

yes. You aren't paying for their mistake. You are paying what you owe pursuant to your contract or lease.

If you are asking do you still owe the rent, the answer is very likely "yes" unless there are some facts that you aren't mentioning. You are not paying for their mistake, you are simply paying what you owe. You owe your rent, period.

If you are asking whether the landlord can penalize you (for example, by imposing a late charge) for your relying on their mistake, that may be a closer question. It would likely depend on whether you were reasonable in relying on the mistake. If it was clearly a mistake and you knew it, you may be on shaky grounds. If it was reasonable for you to believe that the credit was legitimate, then you may have a better argument.