Approximately 3 months of bank transactions missing from Quickbooks. I have checked all tabs and Chart of Accounts Bank Account History. I have dis & reconnected account

QuickBooks Online relies on the information provided by your financial institution. When reconnecting accounts, most banks allow downloads for the last 90 days, while others may offer up to 24 months. Regularly checking your bank connections can help prevent these syncing issues early.

To retrieve your missing 3 months of transactions, you'll need to manually download the statements from your bank's website and import them into QuickBooks. Here is how to upload:

1. Navigate to the Accounting menu and select Bank Transactions.
2. Click the blue tile for the account where you want to upload the transactions. Select the Link Account dropdown and hit Upload from file. 
3. Tick Drag and drop or select files and choose the file you downloaded from your bank. Then, pick Continue.
4. Select the account you want to upload the transactions into in the QuickBooks account dropdown and tap Continue.
5. Follow the onscreen steps to match the columns on the file with the correct fields in QuickBooks. Then select Continue.
6. Pick the transactions you like to import. Choose Continue, and Yes, then Done to confirm.

For more detailed information, refer to this article: Manually upload transactions into QuickBooks Online.

Let us know if you have any other concerns.