How to wipe old Sync data from cloud ?

Product: Firefox for Windows Hello, I am returning to Firefox after many years and have recently reinstalled the browser. I logged into my old Firefox Account, but it immediately started syncing my old data (passwords, bookmarks, extensions) from years ago, which I no longer want. Here is my dilemma: I cannot simply turn off Sync. I want to use Sync for my new data (new passwords and bookmarks) moving forward, so keeping Sync enabled is necessary. I cannot find an option to manually delete old data on the Mozilla account website. The "Delete Synced Data" option mentioned in some older guides does not seem to appear on my current account management page. Is there a way to completely wipe the historical Sync data from the Mozilla servers so I can start fresh with a clean cloud, while still keeping the Sync feature active for my future data? Any advice or solutions would be greatly appreciated. Thank you!