Error 403 when retreiving results

[GianRC]

I have been using the WPT API with an app on Gsheet for several months now, but somehow now it has stopped working.

Somehow now the method UrlFetchApp.fetch in the function getResults with the following url returns a 403 error:
https://www.webpagetest.org/result/231222_AiDc1M_9H2/?f=json&normalizekeys=1

Error :
Exception: Request failed for https://www.webpagetest.org returned code 403. Truncated server response: <title>Just a moment...</title><meta htt... (use muteHttpExceptions option to examine full response)

This happens only when retrieving the results (getResults).

From the browser the same url gets HTTP 200 and the right Json data

Any idea or pointer as to what it might be the issue?