GPT-4 firstly cannot read some large messages, despite both plugins with gpt-4 AND gpt-3 having no issues with the text. Finally I managed to send it some data, and asked it a question about it. But it denied having ever read anything denied being able to read prior messages, and asked for the data. I gave it the data again, and it still claims that nothing was sent. GPT-3 and other models have no such issues.