Bank accounts on my clients QB aren't syncing. In the past I have had to go in and hit update each time and go through security but now even this has stopped working

Hello there, johnl90. 

I'd like to ask on what bank you're working on so I can check here on my end if there are any reported issues similar to it. 

We can also try to manually updating it through a private browser. If you get the same thing I'd suggest contacting us so we can further investigate and we'll work the issue with your bank. 

1. Go to the Help menu and click Contact us. 
2. Enter your concern that your unable to get the latest available transactions from your bank. Please also indicate your bank's name. 
3. Click Let's talk. 
4. Select the Start a chat button. 

Meantime, you can manually upload your transactions into QuickBooks. 

If you have other questions, please let me know.