Drill down doesn't work as expected in api v1.4

Hi guys. I am having some issues with custom visual (api v1,4) related to drill down. https://app.powerbi.com/view?r=eyJrIjoiNjc3NDg1NTUtMzJlMC00MWUwLTg1NzYtMGU4OTQzNDM2NThjIiwidCI6IjAyOWI2YjIzLWZh...