Paypal api – INTERNAL_SERVICE_ERROR while executing payment from paypal in ASP.NET Core

Getting below error while executing payment of paypal:

{"name":"INTERNAL_SERVICE_ERROR","message":"An internal service error
has
occurred","information_link":"https://developer.paypal.com/docs/api/payments/#errors","debug_id":"a997a9f72d8f6"}

Here is the code for payment execution:

var apiContext = PaypalConfiguration.GetAPIContext();
            var paymentExecution = new PaymentExecution() { payer_id = payerId };
            var payment = new Payment() { id = paymentId };
            // Execute authorization.
            var executedPayment = payment.Execute(apiContext, paymentExecution);// Execute the payment
            if (executedPayment.state.ToLower() == "approved")
            {
                var auth = payment.transactions[0].related_resources[0].authorization;

                var capture = new Capture()
                {
                    amount = amount,
                    is_final_capture = true
                };

                var responseCapture = auth.Capture(apiContext, capture);
                return responseCapture;
            }