Namespace prefix is not defined
Declare xmlns:p with the intended namespace URI on the element or an ancestor before using p:name. The URI, not the spelling of the prefix, identifies the namespace. Default namespaces do not apply to unprefixed attributes.
Bind the prefix in scope
Declare xmlns:p with the intended namespace URI on the element or an ancestor before using p:name. The URI, not the spelling of the prefix, identifies the namespace. Default namespaces do not apply to unprefixed attributes.
Reproduced engine diagnostics and complete fixes
Original minimal examples checked on 2 November 2026. Engine wording differs; follow the cause, not a message alone.
libxml2-wasm 0.7.2
Namespace prefix p on r is not definedXerces2-J 2.12.2 / Temurin Java 21.0.13+9-LTS
The prefix "p" for element "p:r" is not bound.lxml 6.0.2 / libxml2 2.14.6
Namespace prefix p on r is not defined.NET 10.0.14 / System.Xml
'p' is an undeclared prefix. Line 1, position 2.Repeat this check in your workflow
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