Error NWK_TABLE_FULL is mentioned in Z2M FAQ and root cause as well as suggested actionable solutions to that is to avoid and reduce EMI/RMI/RMF interference or at the very least try change WiFi channel or Zigbee channel so that they do not overlapp. (It can also help to add more Zigbee Router devices even if not the root cause). Follow these tips:
Zigbee2MQTT documentation also has some of the similar best practice tips but it is not as detailed: