prompts for cell phone verification

This started sometime within the last month or so. (It's Dec 2023 now.) We have multiple emails in our Xfinity account. It is now prompting us, every time we log in to any of them (except for the primary email, to Add your mobile phone number to associate to the email address. The problem is this: the cell phone number must be unique, but we only have ONE cell phone, which we've already associated with the primary email address in our account.

We have no choice but to click on the Ask Me Later button for the non-primary email addresses... and then it follows up with SECOND screen, Secure Your Account, which shows the existing recovery email address (which has to be a non-Xfinity email)...and a place to add a cell phone number, again. Even when I click on the Looks Good button instead of the Ask Me Later, it still does the same two prompts every time we log in.

It doesn't make sense to me that Xfinity asks for a unique cell phone number for each account, when like in our case, we only have one. It's not like we're going to go out and get another cell phone just for this (LOL). But I worry that eventually, it will be a requirement. Can anyone comment on this? Thanks in advance!