Basically, you need to have ALL of the accounts (both Seller and buyer accounts) set on “Payment Review – Disabled”
If you have payment review enabled PayPal won’t clear the fund and without cleared payments the plugin won’t send out digital product links.
The following post will help you solve the pending payment issue in your PayPal account:
https://support.tipsandtricks-hq.com/forums/topic/reasons-for-a-pending-paypal-payment