Nuki hardware bridge and http API Error in hass.io

Hi,

I have a nuki smart lock 2.0 (firmware: 2.4.5) & bridge (firmware: 2.1.37) up and running. The Smartlock works great, bridge is connected and everything works like a charm.

I have set up the API with my token and added the Smartlock to my hass io configuration

The lock perfectly shows up in my frontent of hass io. Let’s assume it is unlocked:
I can click “Lock door” in the hass.io frontend, then the lock closes and I get the following error:

From that point on, the bridge&lock don’t respond anymore when trying to control it from within hass io. Everything else still works - the nuki app, the API commands via curl etc.

I can’t make heads and tails of this. I know this is not a hass io forum, but maybe somebody has an idea?

Thank you!
Malte