In JsonDBTemplate.updateCollectionSchema the JasonWrite function renameKeyInJsonFile is called:
https://github.com/Jsondb/jsondb-core/blob/master/src/main/java/io/jsondb/JsonDBTemplate.java#L402
At this call the collection.values() are passed but not updated.
So if you have multiple renameOperations only the last one takes effect.
The renameKeyInJsonFile-Method should take the PathToCollectionFile instead of the collection.values() and only operate on the JsonFile