Synced the wrong way from desktop anki to anki web and lost all my cards there

I’ve had ankiweb for a year and all of my flashcards are on there for A-level biology but I logged onto my friends macbook and instead of adding her decks to mine, the opposite occurred and all of my ankiweb decks were deleted and her decks from her anki synced to mine. I see in some posts they were able to restore other’s AnkiWeb to its previous state. Would it be possible to do the same for me?
Thanks!

Are there any other devices that you sync with your AnkiWeb account? Those devices might have a more current version of your database.

If not, the most recent server-side backup is from 29 January. Please confirm if you want me to restore that to your account.

There are no other devices, if you could sync those flashcards back to my account i would really appreciate it

Okay, I’ve restored that version.

Keep in mind in the future that any device you sync to this account for the first time will be a one-way sync and you’ll have to choose which collection to preserve. That’s what the very important first-time sync message said, so you should read that before clicking.

You can’t use sync to import decks into your AnkiWeb collection – you’ll need one of the apps for that.

Since your only copy of your collection is on AnkiWeb – make sure you are familiar with AnkiWeb’s data-retention policy. AnkiWeb account removal - Anki FAQs