I'm unable to add my sandbox app V57HY8ZB6KY08 to my test merchant.
Its greyed out and says I need to add as a user, but I'm already the owner.
I've read lots of other posts with this issue and their various solutions. I've tried all the solutions with no success.
My app was installed on my test user. I changed the permissions requirements so uninstalled my app with the intention of reinstalling.
Please advise how to Preview my app and re-install to my test merchant