One or more Revit cloud models in this project couldn't upgrade.
Warning: Couldn't Upgrade Revit Cloud Models
Issue: This could be due to an issue with the upgrade service or an issue with the model.
Solution: Try downloading the individual model to your local machine and do a local upgrade. If this works, contact Autodesk Product Support. If the local upgrade doesn't work, use the information in the error message to correct any issues in the model.
If a model in a project fails to upgrade, all models in the project remain in the Revit release prior to upgrade. You can continue to work in the previous version of the models. If that's not the case or if the upgrade hasn't completed within 48 hours, contact Autodesk Customer Service.