Oh derp, I just saw those yesterday too and I recalled thinking how tedious it sounds ;-;
As long as you don't play away from home the dial-in one would work. I assume you don't have a cell as every cell these days are smart (majority being Android and iPhones are just iPhones) unless you're on a TracPhone... but even those have apps. But I digress.
Definitely protect your account asap. The mobile is just the app, you want the dial-in
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