Ask GPT activity for UiPath is giving blank responses

It appears you are correct, and I am shocked they would do this.

As a replacement for Ask GPT activity, you can now use the Generative extractor through the Extract Document Data activity as part of the DocumentUnderstanding.Activities package available in Studio and Studio Web. The Ask GPT activity itself will be deprecated and will stop working on September 25th 2023. Any workflows still using this activity will stop working on that date.