Bret Question

Thanks a lot. Do you know why?

Yeah Bret was leaving, that is why Vince screwed him out of the title
The below is from Wikipedia which pretty much sums up the situation as far as I'm aware, hope it helps.

-Although Hart had signed a 20 year contract, Vince McMahon had asked him to talk to WCW about possibly taking a second look at their original offer to him, as the WWF was in a rough financial position at the time and could not afford the contract. Hart's final match with the WWF would come in Montreal at Survivor Series 1997. Hart did not want to end his career with a loss to Shawn Michaels in his home country, he asked Vince if he could forfeit the championship the next night on RAW or lose it a few weeks later, which Vince agreed to. Although Hart stated to Vince McMahon he would not take the WWF Championship with him to WCW TV, McMahon had concerns of this and broke his word in what eventually came to be known as the Montreal Screwjob, the most controversial moment in wrestling history. Even though he did not submit to his own finisher the sharpshooter, the referee, on orders of Vince McMahon, had called for the bell as if he had, resulting in Hart "losing" the WWF Title to Shawn Michaels. The night ended with Hart spitting in Vince's face, destroying television equipment, and punching Vince in the mouth backstage.

Yes, he was. He was supposed to win in Montreal and hand over/drop the belt the next night on RAW...But Vince decided he didn't what to chance another Madusa event and have Bret take the WWE title to WCW Nitro.