Late 2012 macbook pro question mark with folder before and after ssd swap

Hello everyone. I'm experiencing a problem with my Macbook pro. My problem started when my laptop crashed and rebooted with a question mark. So i brought it to my universities tech department to check it out and they came to a conclusion that it was a hard drive failure after multiple resets, for a lack of better terms. So they told me to buy a new hard drive. I bought a Samsung 850 Evo ssd and when they were installing it today, they STILL came across the question mark folder. Is there anything wrong with or anything that I can do to fix this? Thank you for your help!