You're right that turning off the custom numbers will reset it back to zero, @Hannah. I've got a workaround for you to continue the old numbering format you're using. 

If you've disabled the custom numbers, turn them back on again. After that, create a new invoice and enter the following number from the old chain. 

Once done, turn off the Custom transaction numbers again. It should pick up the succeeding number moving forward.

I also recommend sending feedback requests to our Product Development Team. They will evaluate these to include in future updates. I'll show you how:

1. Go to the Gear icon.
2. Under the Profile column, select Feedback.
3. Enter your suggestion, then click Next.

You'll want to track your suggestion through this website. You can also visit our blog to keep up with our recent events and developments.

See these articles to equip yourself with personalizing invoices and assigning transaction numbers: 

• Customise invoices, estimates, and sales receipts in QuickBooks Online
• Change the number on invoices or other transactions

If everything's settled, check out this reference to learn how to receive customer payments: Record invoice payments in QuickBooks Online.

Don't hesitate to let me know if there's anything else I can help you with. I'll have you covered. Have a great day.

Hi, I've tried that but as soon as the custom numbers are turned off again, it resets to zero still.

Hi hannah-casswell-, 

This is currently working as designed and the custom number would need to be edited manually after switching back on for the system to pick this back up. We recommend leaving feedback through the option above so that our development team can look at updating this in the future as we do see it can be an inconvenience. 

So, are you saying there is in fact no way of enabling invoices created through WIX to pick up our current sequence?