I had this issue occurring in Xcode 10.3 after I switched over to my XCTest unit test target then back to the project run time target.
Turns out I had a different Teams selected in my provisioning profile for each target.
To fix it :
Clean Build Folder
Make sure all may targets are using the same Team. See Profile Signing under the general tab.
If not using same Team for all targets, clean before switching to a build target with
different team selected.