Warningg: SimpleXMLElement::addAttribute(): string is not in UTF-8

I updated my magento from 2.1.2 to 2.3.2.

Now i am getting below error on my checkout page in luma theme also

Warning: SimpleXMLElement::addAttribute(): string is not in UTF-8 in /vendor/magento/module-shipping/Model/Simplexml/Element.php on line 27

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