ChatGPT saying Unknown Error Occurred for File Uploads

I just upgraded to the Pro plan and not even 3 days in i got this problem, “Unknown error ocurred” only for md, json, pdf files. I have used the normal 20$ version for 3 years and never had this problem. I can upoad pictures, txt files and all types of files saved on library including this ones “md, json, pdf files” so it seems it’s a direct problem with the uploading system. It happens in all types of chats whether is regular chat or Custom Chatgpt.