So far Haaland has not performed as well as last season, he seems to have difficulty scoring many goals this season so Guardiola has to think about that at least so that this season Manchester City really performs well in the UCL and in the domestic league, as we saw in Manchester City's UCL didn't meet a difficult club in group G, but he will meet later against stronger clubs like Munich and Madrid, I think Guardiola has to set a good strategy to be able to make Manchester City play like last season, if you say it looks bad that's which I have seen since their last few matches in the domestic league have suffered unnecessary defeats
Haaland has actually scored 10 goals in 7 games in which he didn't play together with De Bruyne. I mean this statistics covers all the competitions he played in until now. He might have made his second hat-trick against Young Boys in this time period also. As a result everything is going just fine for Haaland now.
Of course there is a really strong bond between Haaland and De Bruyne in-game. Haaland is able to score easier in his presence thanks to his great assists.
This is why Haaland doesn't have the same performance as the last season now. But I still think his performance is good enough for Manchester City now.