Device already exist

[myssv]

I tried to add a new device

I got an error, that the device is already configured

But I can't find it:

What can I do?

I already had the device or the entities in the past

[andrew-codechimp]

Hi,
Have you possibly renamed your battery note? You can rename them independently of the device they're attached to.
When you go into that device (via settings/MQTT integration) can you see battery notes entities in the diagnostics section?
Are there any errors in the Home Assistant logs relating to Battery Notes?

[myssv]

The sensor died and I had to remove it. Then I added a new one ad give him the same name.

Yes it exist at the MQTT integration:

no actual errors visible

[andrew-codechimp]

If it exists on the MQTT device then it must be in the list within the battery notes integration already so no need to add it again.
It's possibly under a different name within the battery notes integration list.
Clicking on batterie+ and looking at its entity id and also the details (attributes) may give you more of a hint.

[andrew-codechimp]

Just a follow up the Device Name attribute of Batterie+ is the name of the Battery Notes entry.

[myssv]

ok, I found out, that there went something wrong renaming the sensor.
Thanks for the hint!

[andrew-codechimp]

Glad you got it sorted, it's very easy to get naming in a mess!