An unknown signal will appear under the deployments tab whenever the Ambi Climate picks up another signal apart from the signal your remote transmits.
Ambi Climate has an IR receive which allows users to continue using the physical remote in conjunction with the Ambi Climate.
However, there are many household appliances/gadgets that also uses infrared as a form of control and communication. This could be a TV remote, a smart home hub, IR controlled light bulbs, dehumidifier or it's the Ambi Climate in the other room down the hall. Sometimes, the structure of the signal is similar to that of your air conditioner or heat pump remote which causes the Ambi Climate to interpret as you using the physical remote to control your air conditioner or heat pump.
Learn more on what unknown signals do to your Ambi Climate and how to resolve this.