How do I resolve this error message: ! Something's not quite right "a is null"?

I can share ways to pass the error and help you reconcile your credit card statement in QuickBooks Online, @accounting526.

Let's perform some troubleshooting steps to fix this. There are times that the browser is full of frequently accessed page resources, which causes some errors or unusual responses. Let's start accessing your account using a different or a private browser. You can use either of these shortcut keys:

• Google Chrome: Ctrl + Shift + N
• Mozilla Firefox: Ctrl + Shift + P
• Microsoft Edge: Ctrl + Shift + P
• Safari: Command + Shift + N

Once you have successfully created reconciled your account, go back to your regular browser and clear its cache. This is done to speed up the process next time you do a transaction in QuickBooks Online. Also, an alternative way is to use other compatible browsers.

I've also added few articles you can refer to for your future guidance and detailed steps in reconciling your account in QuickBooks: 

• Reconcile an account in QuickBooks Online 
• Fix issues when you're reconciling accounts in QuickBooks Online

If you have follow-up questions about it or any other concerns with QuickBooks navigation, please don't hesitate to hit the Reply button below. I'm willing to help and assist you anytime. Take care and stay safe!

Hi, @accounting526.

Hope you’re doing great. I wanted to see how everything is going about reconciling concern you had the other day. Was it resolved? Do you need any additional help or clarification? If you do, just let me know. I’d be happy to help you at any time.

Looking forward to your reply. Have a pleasant day ahead!