Only the last 90 days worth of transactions can be downloaded to QuickBooks Online. If you want to import more than 90 days worth of transactions, you need to contact your bank to check if they offer WebConnect. For more details about importing transactions, you can check out this article: 

Resolution for '2016 transactions issue: 'How can I enter entire 2016 transactions?' available: Yes.

The 2016 transactions issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the 2016 transactions issue yourself by looking for a resolution described in the article. If it is a complex 2016 transactions issue or you are unable to solve the issue, you may contact us by clicking here or by using other 2016 transactions support options.

For more information about resolving issues related to 2016 transactions in Quickbooks/QBO or to get support for the issue 'How can I enter entire 2016 transactions?', click the link below: