Welcome to Trulia!
I apologize for not finding and answering your question much sooner. In the future when you have a question about Trulia, please post it in our Using Trulia category so we can find it right away.
Only listings submitted to Trulia manually can be edited at this time. Though we are working to make all listings editable in the future, currently you'll need to update the source that provides your listing information to us. In your case that source is your web host, Keller Williams. Please contact them to verify that the listing information on their site and in the data feed they send to us is up-to-date. Once they send us any new information, our display should update automatically with that new data.
Please let us know if you have any other questions or concerns.