That was because this is not your topic and you have replied on another user's topic .
Only user who created the topic can see vibethemes staff private replies on his topic .
Please create your own topic and we will continue there .
This was my response in private replies :
I again checked your site today .
I guess this is related to your mysql database.
Please check this screenshot :
http://prntscr.com/gebvlr
same query is working for me on my test setup but its not working for you .
It works when I remove " ' " from '1254' .
As you can see this is site specific issue and is related to something that wplms does not handle which is database .
Its a core wordpress function that we are using which is marking this query . Please consult your host on this .
I would assure if you try this on some other hosting it will work fine coz I have never seen such issue and also this is never reported by someone ever .
Well that is the thing ,there is no error showing up. Its just simply the meta_query is not working .This may be due to your database collation type or database structure .
No other user has reported this issue ever on our forums and also we are not facing this issue .
Its a wordpress query actually which is not working here.
This is site specific issue .
I bet that same quiz will work on another webhost .
I have to remove the meta_query parameter in your site to make it work on your for now .
I would recommend you to try setup wplms on some other host and check this same issue on that .