This is how I got mine to work: let's say your JSON is something like this:
[{""message"": ""Hello World!"", ""fromperson"": ""David"", ""toperson:"" ""manuel""},{""message"": ""Goodbye World!"", ""fromperson"": ""Eric"", ""toperson:"" ""Frank""}]
First, use JSON to Collection. It will come back with a collection that has multiple rows. Each row of this collection is itself another collection (which is why is says something like Row 1 of 1.
Next, we will loop through this collection. This will let us access each row.
Within this loop, use the "Utility - Collection Manipulation" action called "Append Rows to Collection". Your final collection will be the main collection as well as the output. The looped row will be the Collection to Append.
------------------------------
Jordan Bondurant
------------------------------