Issue Duplicate emails

[emilzawislaktsl]

Hello,
I have a serious problem with duplicate emails. Well, I'll try to explain.

In the company, we have an address that works only for redirecting messages. Let it be called [email protected]. This list includes the [email protected] and other employees. The moment I want to send a message to [email protected] and, in particular, to [email protected], this message will come to this employee twice.

Shouldn't there be some security for this? We've been through a lot of mail servers before and never had this problem.
I wrote a message to our hosting provider which is home.pl from Poland and he cannot help me in this matter.

 

[Bitpalast]

Please have a look at the mail server log to identify what is actually happening. Also, have you checked that the recipient is not listed twice in the forwarding list?