Losing items after disconnecting from the server

Hello, today I was playing on the atlas maps and after finishing I wanted to go to my shelter, but I was disconnected from the server.
After waiting for 2 minutes I was able to connect again.
As it turned out, all the collected loot disappeared from the inventory, including the map that I ran through (along with the scarab).
I looked through all my stash tabs and stuff where loot could appear in such a situation, but I couldn’t find it anywhere.

P.S
I just want to return my items (if this is possible to do in some way), if this does not work out, then how can I avoid this in the future? Because due to such errors, very valuable loot can be lost.
Also, what do I need to provide to troubleshoot this issue?

The instance on the server crashed. Unfortunately, there is nothing that you can do about it, it is a server-side issue. GGG are aware of all instance crashes.

Nothing will be returned as per GGG policy.