I just deployed an PERN app on Heroku and during the sign-up process, I receive a 500 http error during the process of saving the image.

Router.post('/upload-image', (req, res) => {

    try{

        // validate if there is an image

        if (req.files === null){
            return res.status(201).json({
                statusRequest: 'ok',
                imagePath: '/uploads/img/avatar.png'
            })
        }

        const image = req.files.file

        image.mv(`../../build/uploads/img/${image.name}`, error => {
            if (error) {
                return res.status(500).json({
                    statusRequest: 'failed',
                    errorInfo: 'Hubo un problema. Vuelve a intentarlo.'
                })

            }
                return res.status(201).json({
                    statusRequest: 'ok',
                    imagePath: `/uploads/img/${image.name}`
                })


        })

    }catch (error) {
        return res.status(400).json({
            statusRequest: 'failed',
            errorInfo: 'Hubo un problema. Vuelve a intentarlo.'
        })
    }

})