Hello,
We have tested it at our end and found no issue as you can see here (https://www.loom.com/share/20b800fe4a8f42b58a936fbe1378129d).
May I know if you have checked marketplace plugin with WooCommerce and standard theme (storefront/twenty). Please deactivate all your plugin, except WooCommerce and WCMp + addon. You can then check the flow. If everything is working fine, in order to detect which plugin is causing conflict- please activate each plugin consecutively and check the flow.
Similarly, for theme conflict- please deactivate the current theme and check with standard WooCommerce theme (storefront/twenty) It is suggested to please perform these tests on your staging website and keep us posted with the outcome.