I can help!
This error usually happens when the transaction isn’t being created in the same database scope as the operations, or when the SDK call returns a transaction object that’s actually null/not committed.
Quick question:
When you call createTransaction(), are you sure it's using the same database ID (68ff00b800318a2a0fa8) you're passing in the operations? Some SDKs require specifying the database when creating the transaction.
If you can share how createTransaction() is implemented in your TablesDB class, I can point out the exact issue.