i just lost an entire month of brainstorming on google AI mode

i was writing a story, it was looking great, i was telling every detail and getting all the ideas, i put a month into this and i loved how the project was becoming, then i had to leave the chat for like 1 week after that month, and when i opened, poof only the first message was present and the AI didn't remember a thing. i am desperate, i copied good part of the thing on Word, but some messages, the first ones, are lost forever. i can't just restart with the middle info i have... i am desperate, this just ruined my day... i feel that i want to cry