If you're saying you switched the account set up for syncing, Zotero would've warned you that it would delete all local data for the old account, required you to check a checkbox saying "Remove all data for “[old account]” from this computer", and said to make sure you either had uploaded any data to the old account before continuing or had a backup of your Zotero data directory.
Assuming one of those is the case, you can restore by either switching back to the old account or restoring from the backup.
I did not have an account set up previously to my zotero. I was just using the app on my laptop for 6 years. I did hit the "remove all data". Is there anyway to revert this and save those files? I cannot find any old version of Zotero on my laptop prior to the sink.
No, you wouldn’t have gotten that message and option unless you had synced with an account previously — it appears solely when you’re switching accounts. (Just setting up syncing for the first time obviously doesn't just delete your existing Zotero data.)
As the message says, you need to have synced with the old account and/or backed up your data before continuing. As long as you did one of those things, you would still have your data. If you didn't, I'm afraid it's gone.
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Assuming one of those is the case, you can restore by either switching back to the old account or restoring from the backup.
As the message says, you need to have synced with the old account and/or backed up your data before continuing. As long as you did one of those things, you would still have your data. If you didn't, I'm afraid it's gone.