Hello there, void a check and bill from prior.

I appreciate you for sharing your thoughts with us. I got your point here.

Voiding both check and bill from prior year will always affect your balances. For now, you'll want to consider creating a Journal Entry or follow the recommendation shared by KhimG. You'll also have to choose what specific year you'd like the changes to affect.

All the resources that you need to know about the whole process are provided by my colleague's above. I'd also suggest seeking professional help from your accountant on what's the best way to handle this situation. 

You can always get back to me if you other questions and I'll be here to keep helping.