I've had this exact problem for the past 3 days with Xcode 10, going around in circles with automatic signing :( wish I had seen your post sooner!!
Can you expand on how you manually signed your application? Did you create and download a provisioning profile or use the latest WWDR certificate?
I've been trying to create a profile for the past hour, but it keeps complaining that there it does not include the selected signing certificate - which is definitely in my keychain.
Appreciate any insights you might have!
Topic:
Developer Tools & Services
SubTopic:
Xcode
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