this is the crash report - Assertion failed: A.ArrayNum >= 0 [File:d:\build++ut+release-next+full\sync\engine\source\runtime\core\public\Containers/Array.h] [Line: 1098]
KERNELBASE.dll!0x0000000024A0A839
UE4-Core-Win64-Shipping.dll!0x00000000E612C74D
UE4-Core-Win64-Shipping.dll!0x00000000E60CC45A
UE4-Core-Win64-Shipping.dll!0x00000000E60754A8
UE4-UnrealTournament-Win64-Shipping.dll!0x00000000DDA262C7
UE4-UnrealTournament-Win64-Shipping.dll!0x00000000DDA388FF
UE4-UnrealTournament-Win64-Shipping.dll!0x00000000DDAE9A03
UE4-UnrealTournament-Win64-Shipping.dll!0x00000000DD75D30E
UE4-UnrealTournament-Win64-Shipping.dll!0x00000000DD81532D
UE4-Engine-Win64-Shipping.dll!0x00000000E48E1359
UE4-Engine-Win64-Shipping.dll!0x00000000E4EA213E
UE4-Engine-Win64-Shipping.dll!0x00000000E4E4E697
UE4-UnrealTournament-Win64-Shipping.dll!0x00000000DD6B2939
UE4-Engine-Win64-Shipping.dll!0x00000000E4E2FE3E
UE4-UnrealTournament-Win64-Shipping.dll!0x00000000DD7D3FB5
UE4-Engine-Win64-Shipping.dll!0x00000000E4E5D56B
UE4-Engine-Win64-Shipping.dll!0x00000000E48E4845
UE4-UnrealTournament-Win64-Shipping.dll!0x00000000DD7D8609
UE4-Win64-Shipping.exe!0x00000000C227FB0F
UE4-Win64-Shipping.exe!0x00000000C227729C
UE4-Win64-Shipping.exe!0x00000000C22772FA
UE4-Win64-Shipping.exe!0x00000000C22803EE
UE4-Win64-Shipping.exe!0x00000000C2280DC3
KERNEL32.DLL!0x0000000026677BD4
ntdll.dll!0x0000000027AACED1
ntdll.dll!0x0000000027AACED1
What keeps going wrong?