Recently I have been unable to use apps which utilize the Lookback API which have worked with my account in the past. After looking at the console, it appears I am getting an Error 403 when the request is being made to the server. I had some co-workers try to access the API as well but we all received the same error.
Is the Lookback API having issues right now? Or is the error on our end?
It appears as though either an "_ItemHierarchy" (RPM) or "_ProjectHierarchy" (Projects) must now be specified. I added the following line to my Lookback API query and the request completed successfully:
{ property: '_ProjectHierarchy', value: this.getContext().getProject().ObjectID }