It appears that Intuit is having a bit of trouble with the audit log and users.

Did you create a user with the same name?

Resolution for 'adding accountant issue: 'adding accountant error' available: Yes.

The adding accountant issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the adding accountant issue yourself by looking for a resolution described in the article. If it is a complex adding accountant issue or you are unable to solve the issue, you may contact us by clicking here or by using other adding accountant support options.

For more information about resolving issues related to adding accountant in Quickbooks/QBO or to get support for the issue 'adding accountant error', click the link below: