i unlink my bank account and when i reconnect it back all my transactions are gone how can i get them back?

Thank you for sharing the detailed process you perform with your bank in QuickBooks before you raised the issue of missing transactions, @cornejoelectric. 

Keep in mind that when you disconnect your bank account in QuickBooks, all transactions in the For Review section will also be removed. Once you reconnect and the entries don't show up, you will need to click the Update tab to reupload them in our software. 

Here's how:

1. Pick the My Apps option on the left navigation and select Accounting.
2. Go to Bank transactions.
3. Find the tile of your reconnected bank and click it.
4. Then, press Update button on the upper right corner.

It is also worth noting that some banks will only let you download the last 90 days of transactions, while others can go back as far as 24 months. 

If this does not work, manually upload your bank transactions in QuickBooks Online for now so you can continue your daily banking tasks. 

However, if all the transactions are missing, including the categorized ones, I'd like to know the name of your financial institution to further help us determine the root cause of this issue since it is not a usual behavior when reconnecting a bank account in QuickBooks. 

You can also log in to your online banking and check for any maintenance or error notification that triggers the issue of missing transactions after the reconnection in our software. Once you confirm that there is one, your bank will provide instructions to fix it within the message, or contact their support directly.

Keep us updated with the result of the troubleshooting and if you need additional assistance retrieving the missing transactions of your connected bank account in QuickBooks. I will be here to help you all throughout the journey.