Activate NOW Internet modem when iphone too old

I've been trying to get in touch with anybody who can simply activate my modem. But in nearly 5 days, I just keep hearing..."...download the app and done." I cannot download the app because my phone OS is maxed out at 15, but the app requires v 17 or higher.
The "assistant" has no way to discuss that issue and is not helpful (after trying at least half a dozen times).

Yesterday, 8-5-2025 at 16:30, I got a hold of an agent who told me that he could send a "ticket" to the NOW Internet team because they do respond to tickets. It would be nice if the NOW Internet portion of xfinity site had that option - submit a ticket.
I was told that they may take a few hours to get to me, but they will respond to the ticket.

Today, 8-6-2025 at 08:00, I have had no response from xfinity and I now have a service for which I pre-paid that xfinity is refusing to support.

My previous account is still active, although it was supposed to be disconnected. If I get disconnected on that account I will have NO Internet access and NO way to work with any AI.

I just want to get my modem activated. Why is that so difficult?