channel should not include both
channel contains two elements which mean the same thing. This can occur in RSS 2.0 when you mix core elements and namespace elements. This can confuse news aggregators and RSS parsers, since there are no universally accepted rules about which element takes precedence.
channel elements that mean the same thing:
language and dc:language
copyright and dc:copyright
generator and admin:generatorAgent
Remove one of the redundant elements.
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