Cannot remove application credential from Credential Vault

Hi. I am running PUM 3.2. I imported DOM-APP-ACTIVE-DIRECTORY_LDAP and would now like to delete it. However, it has a failed check-in. So, when I attempt to delete it from the credential manager, I receive the error message "Please try again. Error Message: You can only delete an account domain when it is not being referenced in the password or shared key checkouts.". How do I fix this?