Could be a docker issue if it works locally, the point is, irrespective of this error being thrown server still returns a garbage corrupt PDF, so it looks like everything is fine, on the frontend, but the tickets don't actually open.
FileNotFoundError: [Errno 2] No such file or directory: '/data/app/static/generated/tickets/attendees/tickets/pdf/5c7e4019-b90a-4100-ab01-3746bc25fdcc/U3V2Wmh2bD/5c7e4019-b90a-4100-ab01-3746bc25fdcc.pdf'