Cannot delete obsolete sensor entity

I created a sensor template to test something in the configuration.yaml.

Later I deleted that code from the config after testing as it was no longer needed.

However even after reboot that entity is still there and no longer updating since it is actually deleted. When I click the settings icon of the entity it says

Blockquote
This entity (‘sensor.abc’) does not have a unique ID, therefore its settings cannot be managed from the UI. See the documentation for more detail.

I am not sure what I can do to get rid of it as I cannot even set it to inactive. I don’t want my setup being cluttered with zombie entities.

Also did you actually reboot the host hardware or restart home assistant?

Rebooting is very rarely required (OS updates mostly).