Help needed with Power Query to get all records from a Rest API using a loop function

Hi there!

I'm just starting out with Power BI and I need to extract data from our online ticketing application to create some reports. I managed to create a query that returns some records with ticket data from selected fields of the past month.

My problem is that the API limits the results to 500 records. So I created a function with a loop to retrieve the rest of the records and combine these in one list. Apart from the 500 records the API returns an additional record with the number of returned records and two URLs. One URL for the previous block of 500 records and one URL to retrieve the next block of 500 records. If there are no more records the second URL returns NULL.

Link to the documentation of the Autotask REST API

I created a function that I call from the query. I did a query count and know there must be 916 records. I'm sure the URL for the next block is passed to the function correctly and I don't get any errors. But the resulting table still shows only 500 records.

I hope someone can tell me what am I doing wrong.