Another time my claim was denied because the agent was unable to type in the correct address. I say "trivago.de",which includes all taxes and fees, they search under "trivago.com", having to convert to EUR and fiddle around with additional taxes. I had a similar case in the past with a Japanese website, where they simply used .com (in English) instead of .co.jp (in Japanese) which I specified.
By on the lookout for that!
HTB.