Need assistance : We can't import and export process in azure devops

Question

We want to import process into or azure devops Organization (board /Process) but the feature is disabled. All permissions are set to be allowed.

Permissions list

We try to import process from rest API:

{
  "$id": "1",
  "innerException": null,
  "message": "The feature is disabled. Contact your Azure DevOps Server administrator.",
  "typeName": "Microsoft.TeamFoundation.Framework.Server.FeatureDisabledException, Microsoft.TeamFoundation.Framework.Server",
  "typeKey": "FeatureDisabledException",
  "errorCode": 0,
  "eventId": 3000
}

How can we perform this action please or enable this feature ? An import button should be available in or organization.

We also tried to import process from witadmin but or organization is in a cloud (not on premise).