My friend has one of Seed Pli strollers. When she traveled abroad it got broken in the hands of the airline she was travelling with. Is there a repair service to asked if it is possible to fix it?
Official repair service of Seed strollers, I never heard of. Any stroller repair service – that exists, but needs some googling, however, there are fewer and fewer of those. You'd do better of with someone who's working with metal if something broke on the frame (if it was plastics, that is pretty much non-repairable).
Overall, though, a broken frame means exchanging the frame 99.9% of the time, and since this model is not really sold anymore, I would try to search in classifieds for someone selling theirs cheaply and used the frame as a spare part.