Could you please check and confirm the version of Lightroom you are using?
In Windows: Click on Help > About Lightroom
In Mac : Click on Lightroom > About Lightroom
Also, please mention which operating system are you using?
Have you tried to use it with any other set of images?
That could be part of the problem. Also, did you overlap the images by at least 1/3? It's usually best to leave your Photoshop work until you have the merged panorama to work on.
I perforned some individual edits in photoshop prior to sending back to LR. Is that the reason I can't merge?
You really want to do this on the original raw files instead of Photoshop edits.
I believe that is the problem. I already edited the pictures before merging.
BTW. I'm using latest LR CC on Mac.
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