FYI, the ZHA integration components in the upcoming Home Assistant 2024.1 will contain a couple ConBee/RaspBee specific fixes (from latest zigpy-deconz library), see → Bump ZHA dependencies by puddly · Pull Request #106756 · home-assistant/core · GitHub
Just to clearify, all Zigbee radios and are very susceptible to interference from strong or close sources of EMF (electromagnetic fields) + have relatively poor range and building material penetration (i.e. bad non-line-of-sight propagation), so you should follow the advice in that guide and take some basic actions to avoid EMF interference by connecting the Zigbee Coordinator USB adapter via a long USB extension cable (preferably one with good shielding) as well as connecting it to a USB 2.0 port or a USB 2.0 hub (and not a USB 3.0 port/hub) + make sure that you have added a few good mains-powered Zigbee Router devices (to extend range and coverage) before trying to connect any Zigbee End Devices (i.e. non-routers like for example battery-operated Zigbee devices). Again, do read and follow this → Zigbee networks: how to guide for avoiding interference and optimize for getting better range + coverage