Issue description
If an Exit GUI Procedure is called, the GUI will not close correctly. The GUI will appear to have closed, but the player will not be able to move until the escape key is pressed.
This can be easily be replicated by creating a procedure that calls for the "Close any GUI open for the current entity" Procedure Block and then creating a button in a Custom GUI that calls this procedure.
1.12.2 or 1.14.4? You did not specify this in the MCreator version.