Jenn Tran had to stop her ex, Matt Rossi, from joining her season of The Bachelorette, according to Reality Steve. She’s already got 25 men lining up to date her – but her past lover won’t be taking part. The Bachelorette season 21 trailer teases Jenn’s ex crashing the group’s travels, hoping for a chance to revive their relationship. “This morning, someone from my past flew all the way here,” Jenn says. Jenn Tran’s ex tries to join showJenn Tran’s ex begs to take back The Bachelorette lead. “He wants to be with me, and he wants to join this journey,” she tells the cast. She was “head over hee…