First, please check to see if the Scope of the rule matches the Scope of the conflict. If you didn't change it, then they should already match. My guess is that you forgot to fill out the InvalidFieldReferenceName datafield, which in your case
should be 'Microsoft.VSTS.Common.Issue'. You can leave the UpdatedConfigurationId blank.
Because you don't have any explicit WorkItemType mappings defined, the radio button (in the non-Advanced section) for 'Update the configuration by dropping the field.' was probably disabled. If you had defined WorkItemType mappings and field mappings,
you could choose this option to automatically modify your config instead of having to use Advanced.
Please let me know if I can help you any further. Thanks.