Can't get these patio rollers out

Here are the pictures I have of the rollers. I know it would be more helpful if the rollers were out of the door, but that is part of the problem. I have replaced rollers before and for the life of me I can't figure out how to remove them. There isn't a screw on the side next to the adjuster, and there are not any visible screws underneath. Any help you could provide me so that I can get them out and ID them so I can buy them from you would be greatly appreciated.

Hi Paul, thank you for the tip. It is a glass door, I saw that on one side of the door are the plastic strips that you can remove, and I'm assuming you can slide out one side of the glass - but are these doors not sealed? Should I get a pro to do this?

Paul,

my mistake, read too quickly. i see that you said it enters from the bottom. I will check, but I was all over that inside with a flashlight, but certainly could have missed it!