Hi @MorningDawnAS, I had this issue before and I know why I got this issue.
This error occurs when your trying to access some information inside a invalid pointer object / variable. For example, if your trying to access information from the player, but the player is not valid. If you force the Engine to get the information you will crash and get this issue.
To avoid this you should always check to see if the object is valid. Sometimes this happen without reason and restarting the project may also fix this issue as well.
Hope this helps! 