I had my full collection of decks on my AnkiWeb. However, they were not synced to my AnkiDroid. I attempted to sync them and lost half of my decks, the same amount that were missing on the AnkiDroid after attempting to sync. How do I retrieve those decks? I research through Google that they were exported so they should be able to be retrieve. I attempted to use the export and import functions on the AnkiWeb (probably messing things up more). To no avail, my decks are still missing. Please advise.
I’m not sure there is a way for you to restore a backup automatically made by AnkiWeb (at least, I couldn’t find it in the manual), but @dae can do that.
There are more cards in your AnkiWeb account at the moment than there were in recent backups, so I presume you have resolved the issue yourself?