PayPal Checkout Plugin

[sohopros]

We are using Joomla 4.4.8, Virtuemart 4.2.12 11014, and trying to migrate to the PayPal Checkout plugin (version 4.2.12)/Payment Method. We were successful in enabling the plugin and adding the Payment Method, but to configure the payment method, we are being prompted to connect the plugin to the PayPal account: "Merchant onboarding here. Use this button to let PayPal configure the plugin or to create an account". This was attempted, and the resulting dialogue box said it was successful, but the data (Merchant e-mail, Merchant id, Client id, and Secret) does not populate into the fields (and cannot be populated manually because the fields are "grayed-out" and inaccessible). Has anyone run into this issue and have any ideas what may be causing this?