AC/Heater fan not working. Please help

So last week i started my truck and no air was coming out of my vents. I could feel heat but it wasn't blowing. I brought it to the shop and they were able to fix it. They said it was only a fuse and they replaced it. But the next day it stopped working again. Again i can still feel heat but it's not blowing. And i can't get in contact with the guy that fixed it because he's not in the shop on Sunday. I'm wondering what the problem might be. I tried putting in a new fuse but it didn't work.