PayPal Expert to Solve Technical Issues

We need someone who is real paypal expert to solve the following issues:

1) Scope Enablement Issue
We are encountering an issue with the enablement of scope for the account. The following error is being generated, indicating an authorization failure due to insufficient permissions. We need to open a support ticket with the technical team to investigate and enable the necessary scope for our account.

setTransactionContext={"name":"NOT_AUTHORIZED","debug_id":"e24388cff2e26","message":"Authorization failed due to insufficient permissions.","details":[{"issue":"NOT_AUTHORIZED","description":"Authorization failed due to insufficient permissions."}]}

2) Transaction Rejection Issue
Following the resolution of the scope enablement issue, we are now facing a new issue where the vast majority of the transactions are being rejected with the error below.

createOrder={"name":"UNPROCESSABLE_ENTITY","details":[{"issue":"PAYMENT_DENIED","description":"PayPal has declined to process this transaction."}],"message":"The requested action could not be performed, semantically incorrect, or failed business validation.","debug_id":"fb9d0376f08be","links":[{"href":"https://developer.paypal.com/api/rest/reference/orders/v2/errors/#PAYMENT_DENIED","rel":"information_link","method":"GET"}]}