When you start D+ on the Roku, isn't it providing a way to log in? It's been long enough since I first installed it, so I can't remember the steps involved. When I added HBO Max last month, It offered a login screen that allowed my to enter my AT&T credentials. If I recall I had to complete the login on a web page, not on the Roku itself. Probably gave me a code to enter on a web page. It then linked to the Roku and away I went.
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