Is this a problem?If so, what to do?

(23:47:39) | standingdriver[866091] changed its network group to null

(23:47:39) | smallboatpassenger[866092] changed its network group to null

(23:47:39) | smallboatpassenger[866093] changed its network group to null

(23:47:39) | smallboatpassenger[866094] changed its network group to null

(23:47:39) | smallboatpassenger[866095] changed its network group to null

(23:47:39) | smallboatpassenger[866096] changed its network group to null

(23:47:39) | rhib_storage[866097] changed its network group to null

(23:47:39) | fuel_storage[866099] changed its network group to null