Duplicate and missing entries on List the company persons with significant control

Hi,
I’m seeing some unexpected results returned when using the query parameters items_per_page & start_index, for example both calls below return the same entry “Mr Daniel Liebert”.

https://api.company-information.service.gov.uk/company/03385619/persons-with-significant-control?items_per_page=2&start_index=6


and
https://api.company-information.service.gov.uk/company/03385619/persons-with-significant-control?items_per_page=2&start_index=2

I’ve seen the same issue with company reference 13244615 when items_per_page is set to 1 and it then returns the same result for both start_index 2 and 4.

It appears to be an API issue but I would appreciate any advise if I’m using the params incorrectly