Sage worst customer support

I am at my wits end! I have for over a year asked Sage to look into why some of my clients do not receive their invoices, even if they DO receive their statements or vice versa. They have kept telling me it is my service provider or my computer. It has now come to a boiling point where more and more people are complaining about this and all they have now been saying for the last month is that they are working on it! Nothing concrete except that we must create, download, save to your computer and email each and every invoice we need to send for month end manually (that we which can do on Word or Excel for FREE). We still have to pay our fees! I understand businesses have technical issues, but the feedback and support we are currently experiencing is unacceptable!