When we click on download invoice, error 500 appears

Job ID: 36298504

Budget: $10 – $30 USD

We need the invoice to be downloadable from our prestashop. When we click on download invoice, error 500 appears. The version of prestashop is 1.7.3. We attach a screenshot so you can see where the error occurs.
Related categories: PHP Website Design eCommerce Prestashop HTML