When trying to send my saml response to the vender I get Element or attribute "cas:75726e3a6f69643a322e352e342e3432" do not match QName production: QName::=(NCName:)?NCName

[Patrick Bennett]

I am trying to send the vendor attribute eduPersonPrincipalName as eduPersonPrincipalName: urn:oid:1.3.6.1.4.1.5923.1.1.1.6

its being salted as <cas:75726e3a6f69643a312e332e362e312e342e312e353932332e312e312e312e36>us...@example.org</cas:75726e3a6f69643a312e332e362e312e342e312e353932332e312e312e312e36> 

then once sent gets 

Error: No principal was found in the response from the CAS server.

2023-04-29 06:50:37,140 ERROR [org.jasig.cas.client.util.XmlUtils] - <Element or attribute "cas:75726e3a6f69643a312e332e362e312e342e312e353932332e312e312e312e36" do not match QName production: QName::=(NCName:)?NCName.>
org.xml.sax.SAXParseException: Element or attribute "cas:75726e3a6f69643a312e332e362e312e342e312e353932332e312e312e312e36" do not match QName production: QName::=(NCName:)?NCName.
        at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:203) ~[?:1.8.0_312]
        at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.fatalError(ErrorHandlerWrapper.java:177) ~[?:1.8.0_312]
        at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:400) ~[?:1.8.0_312]
        at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:327) ~[?:1.8.0_312]
        at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:284) ~[?:1.8.0_312] more of error message