Issue with 1 ZBMini

Hi,

after adding some devices to ZHA i am experiencing issues with one ZB Mini.
I have it connected using an Conbee II and it works as intended, but after about an hour the connection is disconnected.

when i search for Zigbee devices i can add it again and it works again for about an hour, does anyone has an clue where to begin troubleshooting?

Im Using ZHA in combination with Conbee II.