He did give me a B knowledge from Kzarka.
Did reset it 2 time, after the second time I got again a B and then I got a A

You can reset and retry it easy with 2 chars.
Go with one char to Calpheon and reset the knowledge for 10Energy, and log in to your Char at Hakkon. And get the knowledge for 2Energy.
if it is not A+ or S, change back to the other char and remove the Knowledge again.

Amity chain for about 136 favor:
1. Oliviero
2. Lorenzo Murray
3. Vanacil
4. Publio
5. Izaro