Login.Gov/VOIP Issue when using Xfinity VOICE for Verification/Authentication

Is anyone else having issues with using an Xfinity number for verifying or authenticating on government and other websites? I got this message recently from Login.gov when using an Xfinity Number: "This number is a web-based (VOIP) phone service. Please select a different number and try again". I am curious if Xfinity has something provisioned wrong to not flag it as a landline.