What you were expecting to happen, and what actually happened?
All 6 basic tasks have been completed so total armor bonus should be +8. However, in troops menu armor bonus shows only +3
Do you have any screenshots or video you want to share with us so we can see the problem? Attach them to your post!
This is a known bug and will be fixed with the next patch (sometime this week hopefully). Just a display bug. You still get the armor value correctly in battle.
I can go searching for the link if you would like. I believe it was a Nimhaim response in the known issues thread.