I use Monument Lifts and it has an option to deploy a key lock to the car. Will this change it to code locks? The key lock has been a source of problems because players didn't realize they should make extra keys, but could easily attach a code lock when it's off the lift instead.

Nope, doesn't work with monument lifts. It doesn't seem to even work at all.

This plugin works with static lifts last I checked. I can't imagine why that would have changed because both types of lifts function identically.

Did the car you were looting have a cockpit module? Did the player have the permission designated in this plugin? Did the player also have a code lock in their inventory or sufficient resources to craft one? Do you also have the Vehicle Deployed Locks plugin installed?

The requirements and conditions under which the button appears are explained in the plugin documentation. If you meet all those criteria and are still not seeing it, I will help you debug it free of charge.

Yes to all of your questions. To test, I built a small base and placed a functioning lift. Built the frame, placed the modules, had the code lock, had the permission. No option to add the code lock.

I see. If you DM me your Discord username, I can add you and we can do a screen share session when I'm not at work. In the meantime, or in case our schedules don't overlap, it would be helpful to see a video of this reproduction, as well as the output of running Oxide commands to grant the necessary permission.

When I'm on the server next, I'll make a video. To be certain, I ran the o.grant command a second time and it told me the group already has the permission. 

One of the advantages to seeing the whole command is that I can verify it's the right permission: carlockui.use.codelock.

Another thought occurred to me, which is that if you have configured the Vehicle Deployed Locks configuration to only allow deploying locks to your own cars, if the car is not owned, then the UI would not show up. One way to test if that plugin is blocking it for any reason would be to test if you can deploy the lock directly without the UI (using mouse1 while the lock is held), granted that you have the permission in Vehicle Deployed Locks. If you can deploy directly, then that plugin is probably not blocking the UI.

Merged post

If you are still experiencing this issue, could you paste your config for Car Lock UI and Vehicle Deployed Locks? If you are using Craft Car Chassis (you mentioned you "built the frame"), please paste that config as well.