REST API request fail (Error: [] cURL error 28) and Warning: session_start()

@daniel_richard and @kadolf1024,
After months of no response from the plug-in developer, a plug-in update that made no difference, and no luck getting customer support to put me in touch with the plug-in developers, I believe I have resolved the issue myself. Use at your own risk as I am not the plug-in developer, but this is working for me.

Go into the following php file: /wp-content/plugins/easyship-woocommerce-shipping-rates/easyship.php

Find Lines 67-74:

            /**
             *  Register a session
             */
            public function register_session()
            {
                if (session_status() == PHP_SESSION_NONE && !headers_sent())
                    session_start();
            }

And replace lines 67-74 with the following:

            /**
             *  Register a session
             */
            public function register_session()
            {
                if (session_status() == PHP_SESSION_NONE && !headers_sent()) {
	                session_start();
	                session_write_close();
                }
            }

Run Site Health test and the errors should all be gone.