I am trying to connect my Business NextCloud account to my personal (Login to personal, see the Business).
Before, when I added it the first time, I could see all the files and folder in the Business external storage connection in my Personal NC, but after a sync they disappeared from my personal view, says No Files. If I create a folder, it shows up on the Business NC account, and is visible to my Personal, but what was already on the Business account does not show up in the Personal. Via web, desktop and mobile app.
Did this happen after an upgrade from NC 9 to 10? There is nothing in your logfiles I suppose? Can you delete and add the federated sharing?
If you can’t find anything obvious, it may be worth waiting a few days until version 10.0.1 finally gets released (RC1 is currently tested: Help testing the 9.0.54RC1 and 10.0.1RC1). Your issue is perhaps fixed before you dive in a longer debugging session.