[Kane]

https://sampwiki.blast.hk/wiki/OnDialogResponse

You need to define DIALOG_BANLIST and make it do something in there.

I get what you're trying to do but I think it's not going to work. Here's an ideal way of doing it:

PHP код:

public OnDialogResponse(playerid, dialogid, response, listitem, inputtext[])
{
    if(dialogid == DIALOG_BANLIST)
    {
       if (response)
       {
            if(strlen(inputtext) < 3) return SendClientMessage(playerid, -1, "You specified an invalid account name."); 
           new 
                query[128], string[128], DBResult: result;
           format (query, sizeof(query), "SELECT * FROM BANNED Where Name = '%e'", inputtext); 
           result = db_query(bans, query); 
        }
    }
} 


Et cetera, et cetera. Grab the data and store it in a string and show it if the ban exists.