Dictator Mycroft Estine

Hi, new here. I have my own custom flag but have no idea how to change it. I go to my settings and it doesn't give me an option to upload or anything, just pick from real flags. How do I do this?

Application: Nation name: The Mel Reich. Population (may use in-game numbers): 91,675. Population density (may use in-game numbers): 109.14 people/sq. mi Official currency: Euro. GDP (may use in-game numbers): $67,432,049.13 GDP per capita (may use in-game numbers): $735.55 Form of government: Dictatorship. Describe your nation: The Mel Reich is a dictatorship ruled by His Dictatorship Mycroft Estine with an iron fist. In the heart of Europe, the government came to be once it replaced the original Vranica Kingdom through a military coup. It is an authoritarian, police state and it's major industries include tourism, education, and healthcare. Politics & War Wikia link (leave blank if you don’t have one): Have you read, and agree to abide by the rules of the map/subforum? (Yes/No): Yes. Where on the map do you wish to be located? (Using real-world geography, or a self-provided map): Germany. Nation flag link (if you have a specific one you wish to use): N/A. (Map-wise, you're limited to a maximum of 75 provinces. If you go higher than that, I'll personally adjust it down until it's at 75, or ask you to re-do your own example until it fits within the 75 province limit. Note that expansion is allowed, but at a maximum of four provinces per month as to be as realistic as possible. This rule applies to nations under 75 provinces as well. Nations are permitted to own colonies, but at a maximum of 5 with no more than 20 provinces each. Separate colonies are unable to be conjoined. Gifted land is also capped at four provinces per month. This includes land gained by a nation as a result of a war as well.) (You are required to post at least once a month in the national affairs subforum to remain active. This means creating your own topic, not just commenting on your own, or someone else's posts. Inactive nations will be removed from the map.)