71: Target text missing in reference

The circumflex ^ marks a reference to a target on the same page, which is typically located in a footnote. Hence the circumflex needs to be followed by text that identifies the target. This text is missing in your case.

Solution

Make sure ^ is directly followed by the target text which may or may not be enclosed in backticks. The following example uses simply the number 1 as text for setting the target with # and referencing that target with ^:

Henry was the fastest runner.^1

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#1: Unfortunately he often ran in the wrong direction.

If you did not mean to make a reference, but want to use the circumflex literally, you can prepend a backslash: \^