Build for iOS "no private certificate found"

I’m trying to make a developer build for an iOS app.  My problem starts in Corona’s “Build for iOS” window.  Under “Provisioning Profile” I see “Unusable profiles (no private certificate found”.  If I hover over that entry, I see my iOS App ID, followed by “No certificate found”.

I’ve followed the steps in the well-written “Provisioning and Building — iOS” page as closely as I can, and I seem to get the expected results as I progress through the steps.  I have an “iOS Development” certificate, registered my device, have an “iOS App ID”, and have an iOS Provisioning Profile of type “iOS Development”.

In my keychain I see public and private keys for what I’m pretty sure is iOS app development.  I don’t see any kind of entry for the iOS App ID.  (Should I?)

In Xcode, under Preferences -> Accounts -> Apple ID -> Manage Certificates, there’s an entry under “iOS Development Certificates”, but it’s “Untitled” with status “Missing Private Key”.

I’ve searched the interwebs for hours for an answer, and tried to find any topics in the Corona iOS forum that matches, and I haven’t come up with anything.

Help!

UPDATE: under “Provisioning Profile”, the “iOS SDK” combo box says “11.4 (UNSUPPORTED: Local iOS SDK is 12.1 which does not match)”  Could this be the problem?

It’s working.  I tried a couple of different things, and I’m not sure which one solved the problem.

First, I rolled xCode back to the version that has the 11.4 iOS SDK.

Second, I generated my initial iOS certificate from within xCode rather than on the Developer site.

It’s working.  I tried a couple of different things, and I’m not sure which one solved the problem.

First, I rolled xCode back to the version that has the 11.4 iOS SDK.

Second, I generated my initial iOS certificate from within xCode rather than on the Developer site.