Hello Tanya!
Thank you for utilizing the online banking feature in QBO. I'm happy to assist you in adding your missing transactions.
When you connect your bank or credit card account to QBO, only the transactions from the last three months are downloaded. Any remaining transactions will need to be added via manual upload. You can refer to this article for guidance on the process: Manually upload transactions into QuickBooks Online.
After uploading, you can follow the instructions in the Steps 5 and 6 in the article.
Feel free to return to this thread if you need additional help with your bank transactions. Take care and have a great day!