Having an issue with exporting within the WooCommerce Order

 Having an issue with exporting within the WooCommerce Order. I am getting following error when exporting the pdf from woocommerce order

Error: JSON could not be parsed. Go to wp-content/fancy_products_orders/pdfs and check if a PDF has been generated.

Please let me knoe how can I fix that.

Replay me as soon as posible.

Thanks in advance.