You need strong characters, gold especially. If you don’t have a lot of strong characters then wait for them to regain energy before contiuing the PF. Using weaker characters at high streaks will just make you lose and reset.
It may help to have a team of 2 strong characters + 1 weak character to help build up your streak, but once you get around 10 and up that won’t work as well anymore.
Also, try to refrain from fighting turtle teams, like 3 Bella’s or a team with Resonant Evil Big Band.