mySQL查询不返回PHP中连接的结果

I currently have a mySQL query that works in mySQL workbench 5.2, but unfortunately when I translate it over to my php file the CONCAT function is only able to grab FirstName, but not LastName. I am able to retrieve the full name if I don't use the single quotes to build a space between the first and last name, but when I add the code for the spacing, it only retrieves the first name. I currently have a mySQL query that works in my