Multiple usernames for single actor run not working

I am trying to leverage the apify-client for Python to kick off an execution of the Instagram Reel Scraper (apify/instagram-reel-scraper) via API. I have been successful in running this in a "one-to-one" scenario where I run it for a single Instagram handle and it returns ten results as expected. However, I want to be able to pass ~1,600 instagram IDs with a single API call. You can do this through the web console quite easily and it runs without a problem. I can even edit the JSON to execute all ~1,600. However, whenever I try to pass my payload through the API it skips all of the instagram handles. I am curious if it's possible I am not building my payload correctly, or maybe something else. I have been unsuccessful in finding documentation that speaks specifically to the use case I have. I would be happy to read up on documentation if it exists. Thanks in advance!