Qualtrics API - update response (put method) in NextJs

I use the update response (embedded data) API using PHP scripting, and my response embedded data is updated. However when I try to access the API using NextJs I get no updates to the embedded data. Yet the response from the API is status code 200 (all good) along with a requestId. I looked over the API code examples for javascript and jQuery (https://api.qualtrics.com/guides/reference/singleResponses.json/paths/~1responses~1%7BresponseId%7D/put) and what I have coded should work. Here is a snippet of my code (this forum blocked the code when I tried to insert directly into the text field so I was forced to paste into a text file):
UpdateResponseAPI-snippet.txtAny ideas? My other API calls through NextJs (which are similar to this one) work just fine (export responses, get survey details).