Why does Firefly remember previous search words when they are deleted?

When I search for images with a prompt, and change the prompt slightly, Firefly seems to have gotten stuck on old words that are deleted and will not give a new updated image. Trying again with the new words, will often not change the image to what one is seeking.

The solution is often to close everything and start over. 

Seems weird that it gets stuck....please fix that.