Issue 403 Permission error updating Payable invoice Descriptive Flexfield through REST

1:45PM

Issue to update descriptive Flexfield through REST
Summary
Not being able to update descriptive flexfields using patch on payable invoices

Hello,
I have a requirement to update a descriptive flexfield under payable invoices (/fscmRestApi/resources/11.13.18.05/invoices/32209/child/invoiceDff/32209).
When I try to update descriptive flexfield values i got 403 permission erro code. what can I do to avoid this error ?
patch https://xxxx.oraclecloud.com/fscmRestApi/resources/11.13.18.05/invoices/32209/child/invoiceDff/32209

{
"__FLEX_Context" : "Costa Rica",
"__FLEX_Context_DisplayValue" : "Costa Rica",
"laclsCrWithCertificateNumb" : "CNP-00000581",
"laclsCrWhDate" : "18-03-2026"
}
I am using basic auth and already checked roles assigned to my principal. My principal is able to update this descriptive flexfield by using ERP Cloud UI

Issue 403 Permission error updating Payable invoice Descriptive Flexfield through REST

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