Comment 1 for bug 1586070

The @listname syntax uses just a list name in the same Mailman installation, not a list posting address. If you have standard GNU Mailman, this should be just '@list1' in this case.

Please clarify whether this is the issue or if you have a Mailman which is modified to allow the same name in different virtual hosts by appending '@domain' so that the actual list name is <email address hidden>.