If you are using the scanner feature on any of Chekin services for the first time on a Firefox browser, you need to allow the access of the camera.
When Firefox ask for the first time if you allow to use the camera click "Allow"
Important: If you select "Don't Allow" you won't be able to use the scanner and will have to complete the personal data manually.
Re-enable a blocked camera
If your camera is blocked in Firefox or if you denied the access by accident, there's a few steps you'll need to take in order to re-enable the use.
Click the "lock/camera" icon located near the left side of the browser bar, to open the options.
In the "Permissions" section, search for the "Use the camera" permission.
Click the X button next to the "Blocked" or "Blocked Temporarily" text.
Refresh the page to see the changes
After that Firefox will ask again if you want to allow the use of the camera, make sure to click "Allow".
That's it! You should have the camera up an ready.
Note: It's important to refresh the page to see the changes effective.