Thank you for contacting us at Frontier, we are currently in a high traffic period meaning that we may take longer to get to individuals but rest assured that we will get back to everyone.
To provide some clarification on the issue you are seeing, the adjudication server is the in-game mission server.
Server data within Elite Dangerous is transmitted in large data packets opposed to the more common use of multiple packets with smaller amounts of data (seen in other applications) and if your network is not configured to handle these packets (or their fragments) you'll be disconnected with an adjudication server error or be unable to load a complete mission list.
As such can you please check your router settings to see if there are any filters in place, specifically those that mention UDP/packet filtering or fragmented data. Ensure that these are disabled and see if that makes a difference.
Finally due to the large size of packets utilised by the network can you also please try changing the MTU setting within your network to being exactly 1498!
The exact method for altering the settings within your router changes with the model but if you search for the model of router followed by “how to alter MTU” then you should be able to find information regarding how this setting functions!