Hi there, @surendar1.
Welcome to the Community. We can use the Audit Log tool to find the saved invoice. Here's how:
If you're unable to find the invoice from there, that means it wasn't successfully saved. I'd suggest you recreate the invoice and ensure to save it.
For your reference, check out this article: Use the audit log in QuickBooks Online. It helps you keep track of your activities and who made the changes.
If you still experience the same thing, try using another browser. If that works, that means you're experiencing a browser issue. Go back to your main browser and clear its cache to fix the issue.
I'm also sharing this link in case you need some help on how to record invoice payments in QuickBooks Online.
Let me know if there's anything else you need assistance with. I'm happy to be of your service.