Glad to see you here in the Community, heather17.
I'd be delighted to help you match a bank deposit to the paid invoice via QuickBooks Online. Let's get these transactions matched.
To answer your question, yes, you can match a bank deposit to the invoice that has been already paid.
To do that, here's how:
These articles are a good reference:
That's it! Hope I helped you get all straightened out today. Let me know if you still need help with matching your deposits in QuickBooks Online. Have a great day.