Unexpected browsing behaviors can be caused by the saved cache and site history stored in your browser. Let's clear them so you can send your customer's invoice successfully.
To do so, let's start by using a private or incognito window of your browser. You can follow the following shortcut keys below for easy navigation:
If it works, you can clear your regular browser's cache to let it start browsing from scratch. But if not, you can use one of our other supported browser apps instead.
Additionally, you can also browse for the content of this helpful article about the different methods you can start using in accepting payments from your customers: Record invoice payments in QuickBooks Online.
If you have any other questions, you can always leave them in the comments below. I'll be here to address them. Stay safe!