Fedex — Package delivery issues

I have repeatedly asked for FedEx to deliver my packages to my apartment door. I live in a third-floor walkup, yet I am disabled and mange to go up and down the stairs. But my packages from FedEx never get delivered to my door. Instead they are left in unsecured areas of the building where anyone has access to them. I have filled out repeatedly the instructions on where to deliver my packages, but my instructions are ignored. Both Amazon and UPS will deliver my packages where I have asked them to, so what is wrong with FedEx that they won't? I can't believe the laziness and thoughtlessness of the FedEx drivers and the fact that they can get away with this. It's only two flights of stairs, but your drivers must be so out of shape that that is too much for them. Why won't they deliver to my door? And how do I get this resolved? I don't want my packages stolen because they are not delivered properly.