First, pose this question to your own agent and demand that they provide you a defensible answer that sounds plausible to you.
Second, tell your agent to take you to see your 6 top competitors. Those are the 6 other homes in or near your own home that are for sale and are most likely to be considered by potential buyers, in addition to considering your home. You need to know as much about who your competition is (other homes) as possible. Be objective, take notes, and write down why you think the other homes are better or worse than yours. Then be prepared, difficult as it may seem, to adjust your price based on your assessment of how your homes compares to your competition.
What you owe on the home, or what you think it's worth, sadly, is meaningless to buyers. You need to look at your own home the way a buyer would. Going to see your competition, then coming home to your own, is often a good dose of medicine, albeit sometimes hard to take.
By the way, I presume your agent has already provided you with information about the average selling time for a home like yours, and that if you're past the average number of days on the market, they've provided you with a plan on what to do to help move the home. If not, you might need to consider other alternatives sources for selling your home.