X-Request-Id header not passed to upstream API

When creating a HTTP header with the name X-Request-Id we found that the header is not making it’s way to the upstream API. If I change the name to X-Request-Id1 (with a number at the end) then it works fine.

Any ideas what is going on there?

Can you please send us your two versions - the working and the non working?

Please see screenshot attached.

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