"Which office is more decent?" Ha! Ha! What a question! ALL offices are "decent."
Go to any passport and immigration office which is convenient to you and meet the captain. Take with you all the documents. Explain to him the issue and show him the approved visas and your application. The captains are very cooperative, understanding and helpful people. I am sure they will help you out. You don't need an appointment. Working hours are from 6 AM to 6 PM Sundays through Thursdays. Try going to the immigration office located in the Mesaimeer area.