File missing from my Dropbox new version. Can I locate my files after months of being deleted?

I have had a basic version dropbox.com account since 2017, during which time I have created many documents. After about a year of not using this account, I logged into it and noticed that drobox had introduced many changes to its appearance and functionalities. Unfortunately, apart from these changes, I also noticed that my account was empty, I did not have my files that I had created since 2017. I tried to search for them in many ways: through the search engine, in the history, in the deleted files section, in the backup, but I could not find them. By accident, I only found one document that I had created many years ago. What is very strange, when searching the account, both this found file and others (apart from Getting Started with Dropbox.pdf), my account is completely empty. Similarly, when I type it into the search engine, I find nothing. I decided that the new version of dropbox was clearly in beta, it was not fully developed, and I would wait some time. Unfortunately, many months have passed since then and my files are still unavailable. How can I recover very important documents that took me many months of work to create since 2017?