I made the mistake to call all my Homematic IP devices in different rooms pretty much the same (e.g. “Thermostat”) and now this reflects in home assistant as entity IDs with numbered suffix (like thermostat_3).
After renaming the objects in the Homematic IP app and restarting HA, it is still remembering the old entity IDs. How can I delete that “cache” and re-trigger the naming?
Not a HomeMatic IP user, but I would assume those previous IDs are saved in the entity registry. You’ll find that in the .storage folder, in the same location where your configuration.yaml is. Before messing around with the registry you should search the forum for something like move devices from entity registry just to make sure your actions won’t break your whole setup.