Access reading violation when passing object to a class constructor

I'm trying to make a program that makes the camera follow a certain structure of objects by having a "followbehaviour" class, but I get a access violation at the target object when I try to pass the object to the "followbehaviour" class. I'm fairly new to c++ so any help is helpful.

This is the errorcode:

Exception thrown at 0x7C19FF80 (ucrtbased.dll) in mge.exe: 0xC0000005: Access violation reading location 0x00000000.

The structure passed in here is where the error happens

camera->setBehaviour(new FollowBehaviour(*structure));

main.cpp

 GameObject* structure = new GameObject("structure", glm::vec3(0, 0, 0));
structure->add(teapotland);
structure->add(teapot2);
structure->setBehaviour(new KeysBehaviour(25));
_world->add(structure);

camera->setBehaviour(new FollowBehaviour(*structure));

followbehaviour.cpp

#include "mge/behaviours/FollowBehaviour.hpp"
#include "mge/core/GameObject.hpp"
#include "glm.hpp"

FollowBehaviour::FollowBehaviour(GameObject& target):AbstractBehaviour()
{
    
}

FollowBehaviour::~FollowBehaviour()
{
    
}

followbehaviour.hpp

#ifndef FollowBehaviour_HPP
#define FollowBehaviour_HPP

#include "mge/behaviours/AbstractBehaviour.hpp"
#include "glm.hpp"
#include "mge/core/GameObject.hpp"


class FollowBehaviour : public AbstractBehaviour
{
    public:
       FollowBehaviour(GameObject& target);
       virtual ~FollowBehaviour();

       virtual void update(float pStep);

    private:
        GameObject _target;
        glm::vec3 _offset;

};

#endif // FollowBehaviour_HPP

errorcode [![errorcode][1]][1]

if you need anymore code/information feel free to ask. [1]: https://i.stack.imgur.com/jG4wE.png

this works in my main

 Light* light = new Light("light", glm::vec3(0,4,0));
light->scale(glm::vec3(0.1f, 0.1f, 0.1f));
light->setMesh(cubeMeshF);
light->setMaterial(lightMaterial);
light->setBehaviour(new KeysBehaviour(25));
_world->add(light);