There was an article on how DTVNow was merging logins that was written and posted on your site on March 19.. I have seen on a DTVnow forum that I follow for beta tester that the DTV logins are not working with DTVNow. Can you confirm?
Just because they are merging accounts it does not mean you will get access to something you are not paying for. AT&T is merging everything into one account but you still need to pay to access the content. Since you pay for a DIRECTV Satellite service you need to use the app for Satellite TV.