Username and password are case-sensitive, so make sure you have the correct case. Also, make sure you can log in using a browser to be sure the password you remember is correct. Another thing to check is that you are a member of an organization.
Username and password are case-sensitive, so make sure you have the correct case. Also, make sure you can log in using a browser to be sure the password you remember is correct. Another thing to check is that you are a member of an organization.
Are you using the ArcGIS for Portal web adaptor? If so this could be the problem, there was an issue where if Portal for ArcGIS is restarted, then the web adaptor would break. The login to Operation Dashboard would fails in this case especially if you are using built-in security for ArcGIS server. The solution is to re-run the Portal for ArcGIS web adaptor configuration.