Durham was charged to investigate the reason the Trump / Russia investigation was initiated. He determined that there was nothing credible which led to it.
He also stated that the FBI ignored evidence which did not support the collusion narrative
"In short, it is the Office's assessment that the FBI discounted or willfully ignored material information that did not support the narrative of a collusive relationship between Trump and Russia," the report says. "An objective and honest assessment of these strands of information should have caused the FBI to question not only the predication for Crossfire Hurricane, but also to reflect on whether the FBI was being manipulated for political or other purposes. Unfortunately, it did not."