Getting Converted Product and Value from the Facebook Marketing API

I'm trying to extract the Converted Product and Value from the Facebook Marketing API by using Python. I'm running the following code:

fields = ['ad_id', 'ad_name', 'converted_product_quantity', 'converted_product_value']
res = account.get_insights(
                        params={'time_ranges': [time_ranges],
                                'fields' : fields,
                                'breakdowns': ['product_id'],
                                'level': 'ad'})

I do not receive any errors. However, all the AdsInsights object I received only have the fields ad_id, ad_name, date_start, date_stop and product_id. There is no information about the converted_product_quantity and converted_product_value.

Could it be that I'm not using the appropriate combination of breakdowns and fields?