Integrity could not be verified on 'install'

I had an app that was workign fine have a provisioning profile expire…O i logged into the apple site , created a new certificae, and thena new provisioning profile …update the voltbuilder.json and zipped things up and it created a new app for me with no errors. I can instll to my ipad but my customer gets the error about the integrity could not be verified.I rebuilt the app and they still get the same error. Any ideas what I can do to see why it will install and work on my ipad but not on their iphones?
My experience has been that if there are problems in the provisioing profile or P12 file that the app won’t build on voltbuilder. Is that a safe assumption ?

app cannot be installed because its integrity could not be verified”

Are you making a development build?

Do you using a free Apple Developer account?

I found this article which may have some ideas.