2833096 - Verify account with Custom SAML IDP fails in SAP Analytics Cloud (SAC)

• While configuration Custom SAML Identity Provider in SAP Analytics Cloud (SAC), click "Verify Account" button in Step 4, and a red border appears around Login Credential box.  No other error appears or allows to proceed to Custom SAML configuration.
• Chrome console trace shows the error :

{message: "uploadIdPMetadata failed with 500 status", stack: "",…}
bUIMsg: false
bWarning: false
errorDetails: [{message: "uploadIdPMetadata failed with 500 status", bUIMessage: false, bWarning: false}]
message: "uploadIdPMetadata failed with 500 status"
stack: ""
status: 500

• SAP Analytics Cloud 2019
• Custom SAML IdP

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