I have an iPhone 6+. I’m trying to download fb messenger specifically, but have the same problem for all apps. I click on install and a message appears saying, “ click continue and and sign in to view billing information”. There is no “continue option”. I have tried to update but same message. I have changed password in iTunes and turned off password required in settings. I was at one point given a “continue” option and it still did not work. I cannot download any apps.