Ive deleting some invoices by mistake which i havent claimed the vat back on?

I've got you the steps to recover the mistakenly deleted invoice, @kbrooks55.

We can check your Audit Log to get the details of the deleted invoice. Then, recreate it.

To access the audit log, make sure to sign in as admin and do the following steps below:

1. Go to the Gear icon.
2. Select Audit log.
3. Use the fields on the page to choose the appropriate User, Date changed, or Events filter to narrow the results. 

Once done, recreate the invoice using the data you've gathered.

For future reference, visit our Reports Help Articles for QuickBooks Online to monitor your sales and other income transactions effectively.

Come back to me if you need more help. I'm always around to guide you.