I just like to say something in sympathy to the OP. The last 3 services my folding bike had, there were major, dangerous things left undone. The first two services by people that were unfamiliar with my bike model, they left bolts loose, that could have made the bike fall apart. The 3rd service was done by a shop that knew my bike model well. They didn't leave any bolts untightened, but after replacing chain, derailleur, cassette and back wheel, they never adjusted the hi/lo screws, which could have had disastrous results. So, I started maintaining it myself. There was a fault that I was aware of, but decided was ok. It wasn't. The bike folded on me while riding it, I've broken my clavicle and it's probably going to require surgical intervention. It's no one's fault but mine. It's true that all of the other maintenance errors could have lead to the same result, but they didn't. I'd rather have destroyed a £1000 bike, than done this too myself, but here I am, broken. and no amount money will get me back the way I was, with out a scar or two and at least 6 weeks rest.
You are probably going to have to write this off to experience. At least you weren't (badly?) injured in the failure.