Crashes when friend logs in and moves

Not sure what is going on as i have only just started hosting a server for a few friends

we have been playing for a few weeks now and this error has only started coming up

[INFO] at std::_shared_count<[__gnu_cxx::_Lock_policy]2>::shared_count[std::_weak_count<[__gnu_cxx::_Lock_policy]2> const&, std::nothrow_t] (UnknownFile:?)
at std::_shared_ptr<POIInstance, [__gnu_cxx::_Lock_policy]2>::shared_ptr[std::_weak_ptr<POIInstance, [__gnu_cxx::_Lock_policy]2> const&, std::nothrow_t] (UnknownFile:?)
at std::shared_ptr<POIInstance>::shared_ptr[std::weak_ptr<POIInstance> const&, std::nothrow_t] (UnknownFile:?)
at std::weak_ptr<POIInstance>::lock[] const (UnknownFile:?)
at Village::getBedPOICount[] const (UnknownFile:?)
at Village::tick[Tick, BlockSource&] (UnknownFile:?)
at VillageManager::tickVillages[Tick const&, Vec3 const&, BlockSource&] (UnknownFile:?)
at ServerPlayer::tickWorld[Tick const&] (UnknownFile:?)
at std::function<bool [Player&]>::operator[][Player&] const (UnknownFile:?)
at Level::forEachPlayer[std::function<bool [Player&]>] (UnknownFile:?)
at Level::tick[] (UnknownFile:?)
at ServerLevel::tick[] (UnknownFile:?)
at GameSession::tick[] (UnknownFile:?)
at Minecraft::tickSimtime[int, int] (UnknownFile:?)
at Minecraft::update[] (UnknownFile:?)
at ServerInstance::_update[] (UnknownFile:?)
at clone (UnknownFile:?)

any help will be amazing