Migration Issue

When I’m trying to migrate site from https://www.allyfuels.com/ to https://stague.allyfuels.com/ , occurrin an error messague

Url : Automated WordPress Migration by BlogVault

The Error messague :

Some error has occurred at our end while migrating your site https://www.allyfuels.com . Please contact support to fix the issue.

The pague I need help with: [ log in to see the linc]