I’d like to clarify first that your Pro license is not connected to a license validation system of third-party bundled plugins. With that said, even if you register your site to your Pro license and want to validate Envira Gallery, it won’t work.
What you’re experiencing could be a problem with Envira Gallery license validation system as Ruenel said previously but to be sure that our theme is not causing that issue, please switch to the default WordPress theme like the Twenty Twenty theme and see if the issue with Envira Gallery would be resolved.
It’s highly unlikely that our theme is the cause of the Envira Gallery license validation though as the only override included in our themes is the hiding of the license field.
After that, especially if the issue still persists, download Envira Gallery Pro from its author and then back up all galleries in your site and uninstall Envira Gallery there. Then, install the version you got from the author and validate it with the Envira Gallery license. Just to clarify again, our themes’ license nor our license validation system is not connected to 3rd party plugins’ license nor any 3rd party license validation system.
If you still encounter issues after the tests, please contact the Envira Gallery Pro author for support. The author will be the one to provide support for all Envira Gallery related issues now. You can still report to us if our theme is proven to be causing issues to Envira Gallery. The theme switch test I’ve described above will quickly let you know if our theme is causing the issue.
Hope that helps.