A realtor said she’d take out an ad to help me rent my New York City apartment. Am I now morally obligated to use her?

“Other agents know our apartment is available for rent and now want to show it.”

A realtor said she’d take out an ad to help me rent my New York City apartment. Am I now morally obligated to use her?
“Other agents know our apartment is available for rent and now want to show it.”