Due to Home Assistant limitations it is possible that you will get message “401: Unauthorized” in card or panel.
Example how this error can look like in image bellow.

SOLUTION 1: #
You need to do this every time when you login to Home Assistant from new device -> open add-on from left sidebar.
After opening add-on on this way, you will be able to see 3D visualization in panel or card.

SOLUTION 2: #
You need to do this every time when you login to Home Assistant from new device -> follow steps:
1. Settings
2. Add-ons

3. select Klet3D by GLAMOS

4. click on Open web UI.

After opening add-on on this way, you will be able to see 3D visualization in panel or card.