Bad Certificate for UWP app (Error code 0x800B0109)

I've created a UWP app using Xamarin Forms in Visual Studio. It is ready for release, and I do not intend publishing it to the Windows Store. Under the "Packaging" tab of Package.appxmanifest, I created a test certificate via

Configure Certificate... >> Create test certificate...

and then created the app package. I can install the application on my own device (that was used to create and publish the app) using the .appxbundle file in the package, but any other device will not install the app, saying that "Either you need a new certificate installed for this app package, or you need a new app package with trusted certificates. Your system administrator or the app developer can help. A certificate chain processed, but terminated in a root certificate which isn't trusted (0x800B0109)"

On the devices giving this error, I have installed the certificate using the Certificate Import Wizard to both the local machine's "Trusted Publishers" and "Trusted Root Certification Authorities" stores, as well as whatever stores were chosen using the automatic option, then restarted the device. When I go into Digital Signature Details under the .appxbundle file's properties, it says that "The difital signature is OK", but still gives me the same error when I try to install the app.

If there is an issue with my certificate, which says it expires on 1/7/2019, how can I create a certificate that will work? Otherwise, have I incorrectly installed the certificate on the device? I have double and triple checked and the device is set to Developer Mode. It is also on the same version of Windows 10 that my device is on.

I have also tried right clicking the .ps1 file and running with powershell, which gives me the same error. I have been following these instructions to this point: https://docs.microsoft.com/en-us/windows/uwp/packaging/packaging-uwp-apps#before-packaging-your-app

I've discovered the issue on my own. I had mistakenly installed the certificate to "Third-Party Certification Authorities" instead of "Trusted Root Certification Authorities". Once I installed the certificate to the proper stores the app was able to install.