AADSTS501241

Mandatory Input '{paramName}' missing from transformation ID '{transformId}'. This error is returned while Microsoft Entra ID is trying to build a SAML response to the application. NameID claim or NameIdentifier is mandatory in SAML response and if Microsoft Entra ID failed to get source attribute for NameID claim, it returns this error. As a resolution, ensure that you add claim rules. To add claim rules, sign in to the Microsoft Entra admin center as at least a Cloud Application Administrator, and then browse to Entra ID > Enterprise apps. Select your application, select Single Sign-On and then in User Attributes & Claims enter the Unique User Identifier (Name ID).