Honda 3011H keeps throwing deck belt, why?

[Honda 3011H]

I have a Honda 3011h that was always great, it always starts and it used to always work. Then it threw its drive belt and due to the fact that the tensioner for the main drive belt is so incredibly strong I was unable to reseat the belt. I took it to a shop and they put on the new belt and a guard for the belt assembly. Ever since then it seems to throw both belts constantly, and it’s destroying the deck belt. The deck belt has also inverted its self several times. I’m really at a loss.

 

[bertsmobile1]

At a guess they have fitted the wrong belt.
Once a belt inverts it is destroyed so needs replacing again
If a new belt jumps off then there is a problem with alignment or you bent one of the pulleys trying to roll the belt on or one of the pulleys is damages or a bearing is damaged
etc etc etc