Paypal Setexpresscheckout ItemDescription Grails

I can't set the item summary in set express checkoput. L_NAME0=A caused error

        def strUsername = "***"
        def strPassword = "***"
        def strSignature = "***"
        def strCredentials = "USER=" + strUsername + "&PWD=" + strPassword + "&SIGNATURE=" + strSignature
        def strNVPSandboxServer = "https://api-3t.sandbox.paypal.com/nvp";

        def user = session.userId +","+amt + "," + receiver + "," + address + "," + opt 
        def successUrl = '*** 

        def cancelUrl = '***'
        def strAPIVersion = "56.0"
 def strNVP = strCredentials + "&ME开发者_如何转开发THOD=SetExpressCheckout&AMT=" + totalamount +"&PAYMENTACTION=Sale&RETURNURL="+ successUrl+"&CANCELURL="+ cancelUrl +"&CURRENCYCODE=SGD&ITEMAMT="+totalamount+"&L_NAME0=OHN&VERSION=" + strAPIVersion

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Try updating def strAPIVersion = "56.0" to def strAPIVersion = "76.0" I think the advanced features a not available in the 56 version. I used the default set by Paypal as a test &L_PAYMENTREQUEST_0_NAME0=10% Decaf Kona Blend Coffee
&L_PAYMENTREQUEST_0_NUMBER0=623083
&L_PAYMENTREQUEST_0_DESC0=Size: 8.8-oz &L_PAYMENTREQUEST_0_AMT0=9.95
&L_PAYMENTREQUEST_0_QTY0=2
&L_PAYMENTREQUEST_0_NAME1=Coffee Filter bags
&L_PAYMENTREQUEST_0_NUMBER1=623084
&L_PAYMENTREQUEST_0_DESC1=Size: Two 24-piece boxes
&L_PAYMENTREQUEST_0_AMT1=39.70
&L_PAYMENTREQUEST_0_QTY1=2
&PAYMENTREQUEST_0_ITEMAMT=99.30
&PAYMENTREQUEST_0_TAXAMT=2.58
&PAYMENTREQUEST_0_SHIPPINGAMT=3.00
&PAYMENTREQUEST_0_HANDLINGAMT=2.99
&PAYMENTREQUEST_0_SHIPDISCAMT=-3.00
&PAYMENTREQUEST_0_INSURANCEAMT=1.00
&PAYMENTREQUEST_0_AMT=105.87
&ALLOWNOTE=1