Game crash and error message

Game mode: [Online | multiplayer]
Problem: [Crash]
Region: EU

I have a problem every time i play on a friend server, i crash. it can be hours into to game and it can be minutes. Im not doing anything in perticular, jumping around, standing stil, building, in a fight, doesnt matter. This is the error code i get:
Fatal error: [File:C:\UE4\CSAND\Engine\Source\Runtime\CoreUObject\Private\Serialization\AsyncLoading.cpp] [Line: 6615]
LoadPackageAsync failed to begin to load a package because the supplied package name was neither a valid long package name nor a filename of a map within a content folder: ‘’


Steps on how to reproduce issue:

My friend is getting the exact same error when playing coop with me hosting