API returns 502 when accessing certain eventsignups with users embedded

Created by: marcoep

Steps to Reproduce

1. login as user noah, get token
2. do an authenticated GET request to the following URL: https://amiv-api.ethz.ch/eventsignups?where={"event":"59e5fc1fedcb11000ae5ecd9"}&embedded={"user":1}&page=5 a 502 should appear
3. If you change &page to 4 or 6, the API replies correctly.

Expected Behavior

Return the eventsignups number 101 to 125 for the Noahs Wurstparty event.

pls fix