ip6 addresses

I am having a bit difficulty after the new upgrade.
I want to change apache listening port at the following page.
Webmin
Servers
Apache Server
Global Config
Networking

However, there is a new field which is 2a01:4f8:190:8091

I want it to listen on port 8080 like my other regular ip adress. Currently it is on port 80
However, when I try to change port, it gives me an error stating that

2a01:4f8:190:8091 is not a ip address.

Failed to save Networking and Addresses : ‘[2a01:4f8:190:8091::2]’ is not a valid address for name virtual servers

But it is already there listening on 80

Thanks.