Your plane's too small.
Your company has a certain amount of overhead -- expenses that must be paid whether you fly 1 plane or 10 planes. Since you're only flying a single plane, you're not getting much money in to pay for all those expenses. You've got to pay your marketing people, you've got to pay all your headquarters presidents, vice presidents, and so forth. You've got a lot of expenses that need to be covered before you ever make a profit, and a single tiny plane flying a few times a day isn't going to cover them all.
Basically you need more planes. Lot more.
You're also flying to new destinations before you fill up demand at others. You've got MASSIVE amounts of available demand going into ATL, enough to fly 20 times per day to with your little plane, but you're opening more new routes at other airports instead. Fill up the demand somewhere before you look elsewhere. About the only time you might want to reconsider doing that is it simply gets too expensive to acquire any more slots on that route (slot fees get higher and higher the more you monopolize a route).
For every route you open, again, there's more overhead expenses to running that route. A single little plane flying once per day isn't going to cover the expense of having baggage handlers, gate people, customer service agents, marketing people, etc, etc, etc that you have to pay to operate that route.