Failed to return the offline license. ArcGIS Pro cannot be set to work in online mode

Error Message

When using ArcGIS Pro within an ArcGIS Enterprise environment, attempts to return a license to Portal for ArcGIS fail and return the following error message:

Error:
Failed to return the offline license. ArcGIS Pro cannot be set to work in online mode. Please contact your organization's administrator.

Additionally, on the Portal for ArcGIS homepage, when navigating to:

• Organization > Licenses > 'View license activity', the label displays the Disconnected status.
• Organization > Licenses > Manage under the assigned ArcGIS Pro license level, the toggle button is disabled with the Included remark.

Cause

• The license is offline on another machine that is inaccessible.
• A new Portal for ArcGIS deployment is deployed while the license is taken offline.
• Changes were made to the machine, causing the corruption of the license. For example, the ESRI_Licensing folder is deleted or modified, or the license folder in Registry Editor is altered.

Solution or Workaround

Release the checked-out license. Refer to ArcGIS Enterprise: Release a checked-out license for instructions.

Note:
If the issue persists, recover the license from My Esri. Refer to How To: Recover lost licenses from My Esri for instructions.