Hello @jpduchesneau,
Instead of Array Aggregator use Text Aggregator to combine all mail content in a single string with proper context.
When you directly pass the Aggregated array result to GPT they consider it as a collection instead of a string. That’s why GPT can’t understand the context.
Another very important thing is to give proper context to your GTP prompt. Also, tell them this is my type of input and I need output in this specific format.
The prompt is always a combination of Input, Process and Output.
Example prompts
https://platform.openai.com/docs/examples/default-meeting-notes-summarizer
https://www.reddit.com/r/ChatGPTPro/comments/13n55w7/highly_efficient_prompt_for_summarizing_gpt4/
Also directly ask in GPT UI.
P.S.: Always search first, Check Make Academy. If this is helpful, Mark Best Answers as Solutions 
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