Board Game Arena

I met an error like this while "Full game model synchronisation" section in Hearts tutorial:

Unexpected error: Wrong formatted data from gameserver 1 (method: createGame): JSON_ERROR_SYNTAX
Warning: Undefined variable $query_values in /var/tournoi/release/games/hearts/999999-9999/modules/php/Game.php on line 362

what's mean...??
please help anyone...!!

I believe query_values is something that comes the template project. Maybe you deleted some necessary code. The error is saying somewhere $query_values is used but it was not defined on a previous line as in $query_values = something or other. In my tutorial code, the variable is used near the beginning of the function setupNewGame.