Cannot connect to DeconzBridge under Homeassistant: Invalid JSON

I am using a Conbee II stick with Deconz 6.19.0 under Homeassistant 10.0, and used to be able to connect the Hue essentials app (version 2.1.1) through the 40850 port. Since about a week ago, I lost the connection and when I try to connect manually, I get this error message:

Unexpected response from bridge.
Please try again later

Invalid JSON at 160793: Expected string or non-null literal.

JSON input: …time":“W127/T12:10:00”,“name”:null,“recycle”:false,“status”:…

Does anyone know why this suddenly appeared and how to fix it? I was really happy with the Hue Essentials app.