only the first foot note is correctly marked.

[kenhan]

The following snippet:

 This is the first footnote.[^note1] Here's some text.

 This is the second footnote.[^note2] Here's some other text.

 This is the third footnote.[^note3]  Here's some other text again.

 This is the fourth footnote.[^note4]  Here's some other text many more times.

[^note1]: Hello.
[^note2]: World.
[^note3]: See you later.
[^note4]: Good bye.

produces only the first footnote correctly interpreted, and the rest show up uninterpreted as:

1. Hello. [^note2]: World. [^note3]: See you later. [^note4]: Good bye.  ↩

What am I doing wrong?

[fletcher]

Use a blank line between footnotes