You have a couple of options that I can suggest.
One would be to rent it out, if you can get enough to cover the mortgage, taxes and insurance.
You can also list it for sale. If you have money to pay the difference, between what you owe and what is due, then you can sell it outright. If you don't have the money to pay the difference, then you can attempt to do a short sale. This is where the bank accepts less than is owed. The banks are looking at what kind of financial hardship you may have that would prevent you from repaying the debt. Typically this is something like job loss, medical bills etc, not a desire to move to something different.
If you need someone to take a look at your condo and give you an idea of where it might sell and let you know more about your options, I would be happy to talk with you.