configuration error after upgrading to 13.1.1

Hi,

just updated our F5 from 12.1.2 to 13.1.1. Unfortunately I have an issue with one VS in the internal partition, it is disabled and it's not possible to enable it.

The error that occurs is following:

Configuration error: Virtual server (/Internal/Exchange2010-Internal.app/Exchange2010-Internal_combined_https) with access profile attached has traffic group (/Common/Internal-TG) that is different from existing one (/Common/External-TG)

We have 2 partitions (Internal / External) and also 2 traffic-groups (Internal-TG / External-TG), where all the VS are assigned properly. With 12.0 / 12.1 everything worked fine, also after updates. Now, after upgrading from 12.1.2 to 13.1.1 this error occurred, but only in the internal partition. The External one has also an OWA-VS created with the same iApp - everything ok there.

I checked all the configuration, unfortunately I can't find anything that could be wrong by myself. The configuration was done with an iApp and later some changes were made, but nothing special and nothing that could describe such an issue.

Any ideas?