Hello there, @rameet,

There isn't an option to revert an invoice once voided.

As another workaround, you can use the Audit log to view the details and re-enter the voided transaction.

Here's how to locate the invoice:

1. Click the Gear icon.
2. Under Tools, select Audit Log. 
3. Select the exact User, Date, and Events filters from the Filter drop-down.
4. Click Apply. 
5. Locate the voided invoice.
6. Under the History column, click View. 
7. Use the information from the Audit History when you create a new invoice with the same information. 

Please check out to this article for additional information with voiding or deleting transactions in QuickBooks Online: How to void or delete an invoice or other transactions.

Keep me posted if there's anything I can help you with navigating your sales forms in QuickBooks. I'm always around whenever you need help.