Launching and packaging does not work

I have had this problem for a while now and don’t know how to fix this issue. Every time I try to launch or package my game it doesn’t work. A screen shows up and says the following:

The UE4-Delusion Game has crashed and will close

Assertion failed: RecursionNotAllowed.Increment() == 1 [File:D:\Build++UE4\Sync\Engine\Source\Runtime\CoreUObject\Private\Serialization\AsyncLoading.cpp] [Line: 4410]

Attached is the crash client after launching the project. link textPlease help me solve this, much appreciated.

Apparently I have fixed this issue (I think) by turning on Async Loading. Then when I tried to launch the game, this message showed up:

Assertion failed: IsInGameThread() [File:D:\Build++UE4\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\UObjectGlobals.cpp] [Line: 1050]
Unable to load /Game/Blueprints/Widgets/Main_Menu/Audio/Audio_General_Class. Objects and Packages can only be loaded from the game thread.

Now I am currently stuck, any help is much appreciated. Thanks