Hi,
There are a couple of factors that go into this:
-You will see the +10% in the ships infocard ONLY as additional average weapon damage, not listed as a seperate buff at the bottom of the card.
-Ensure you have active peace treaties with the friendly forces in question. Just being on your team is not enough to gain the +10%.
If you are still having an issue, we will look into it further.
Regards
