Forwarding doesn't work for mails with false mail addresses

Forwarding doesn't work for mails with false mail addresses

Dear forum users,

I have the following issue: I have an alias mail address, and I want all e-mails coming to this alias address (it is mostly Spam) being forwarded to another mail address.

I set up a mail filter according to that, but it doesn't work when the sender hides the real recipient address. I just see in the details that they have been sent to the alias mail address for which I have the forwarding rule.

Does anybody have an idea how I can manage that all e-mails received by this alias mail address will be forwarded?

Thanking you in advance.

Kind regards