Exhaust system was replaced 2.5 years ago and now the mid pipe flex section is leaking already with the rest of the system in good shape. Any way to repair it without having to buy a whole new section?

 

I believe you are talking about the braided stainless steel flexible joint between the engine exhaust and the rest of the exhaust system. That flex joint is there because when the engine moves as you step on the gas it allows the rest of the exhaust system to remain somewhat stationary. If it was not there the entire exhaust system would have to move more than it normally does and this places a lot of stress on all the parts .
Just think how much the manufacturer could have saved if it was not there, but you would be replacing pipes and clamps on a much sooner time interval.
They aren't that expensive and it is a wise move to replace it ASAP since the fumes that are leaking out will find it easier to leak into the vehicle and that's not a good thing in the cold weather when all the windows are closed and the heating system is pulling those fumes from the leak into the vehicle.