Unable to access uploaded files in specific chats

Hello, I’m a paid user and I have a long chat where I am analyzing data and brainstorming building a pilot program for my community. I used to be able to upload files here but it suddenly stopped a week ago and I keep getting errors now. Either the upload button is greyed out or it errors with: “It seems there was an issue processing the file. Could you please re-upload it? I’ll analyze the data and calculate the confidence improvement levels as soon as I have access. Let me know how you’d like to proceed! ​” then I try again and it says “It seems there’s still an issue accessing the file.”

I have downloaded the Chat open AI client and have tried on two browsers and I get the same issue in all places. I am able to upload files in a new chat, but I need the history from the old chat.

Now it’s not working in my new chats either. The new message is: It seems the file is still not accessible due to a technical issue. Could you describe any specific fields or share the data summary again, and I’ll attempt to assist without directly using the file? Alternatively, you could share the relevant columns as plain text or a simplified file.