Debug PayPal payment on WordPress / woocommerce

Currently in our WordPress website, payments are made by card and PayPal.
Woocommerce is linked into our royal mail click and drop account.

So all orders from our website automatically listed in our royal mail account for label printing

Orders paid by card are coming through fine. But orders via PayPal are not coming through on woocommerce and not listed in our royal mail account

This error needs to be fixed