How can I remove an electronic payment assigned to an invoice

Hi there, 

I was paying invoices via the Pay Bills section using the "Group with electronic payments" Option and when I went to "Prepare Electronic Payments" I realised that one of my invoices was incorrect. How can I remove the payment to that invoice so that I can do it again with the correct amount? 

I gues I mean how can I change its status from closed to open again so that it can be changed?