Why spyOn function is not executing

Question

I' testing endpoint

router.post("/changeRadius", async (req, res) => {
    try {
        const radius = req.body.radius;
        const id = req.body.id;
        if (radius === null)
            return res.status(400).send({message: "Nie podano nowego promienia"})
            
        const updateRadius = {
            radius: radius
        };
        
        await models.user.update(updateRadius, {
            where: {
                id: id
            }
        })
        res.status(201).send({ message: "Promień został pomyślnie zmieniony" })
    } catch (error) {
        console.log(error)
        res.status(500).send({ message: "Nie podano nowego promienia" })
    }
})

The test looks like this

it('should handle server errors', async () => {
        jest.spyOn(models.user, 'findOne').mockImplementation(() => {
          throw new Error('Błąd bazy danych');
        });
    
        const res = await request(app).post('/api/users/changeAlias').send({ alias: 'someAlias', id: 1 });
    
        expect(res.statusCode).toEqual(500);
        expect(res.body).toHaveProperty('message', 'Błąd serwera');
});

It's working when i normally close the connection with db (sequelize.close()), but i want to use spyOn, it gives the 201 status instead of 500 so the spyOn function doesn't even execute.