how can i fix an application error i receive when trying to edit an existing or add a new customer for an invoice?

Thanks for reaching out, AK. We value your proactive approach in addressing this matter.

To resolve this issue, I'd like to connect you directly with our Live Support team. As this is a public forum, they have the needed tools to securely access your account and investigate the underlying cause of this unusual behaviour. We're here to help ensure everything runs smoothly for you.

Here's how you can reach them:

1. Sign in to your QuickBooks Self-Employed (QBSE) account.
2. Go to the Help (?) icon.
3. Click on the Assistant tab, then enter and send Talk to an expert.
4. Provide a brief overview of the issue you need assistance with.
5. Choose your preferred method of contact.

You can head over to this page for our Live Support team's availability and select a time that's most convenient for you: Support hours.

In the meantime, you can hop into the mobile app to add any new customers or make changes to existing ones in QBSE.

Feel free to reply to this post if you need further assistance.