Cox App outage alerts - "Please enter a valid phone number."

In the Cox App, both a couple of weeks ago and today, when I attempt to "Sign Up for Text Notifications" about an outage, I input my phone number, and the app says "Please enter a valid phone number."

I understand there are workarounds: I can sign up for text alerts via phone; or via a PC web browser if internet is back briefly. I've already signed up for text alerts for the current outage. I am reporting this feature of the app not working so it can be investigated and fixed; not only for myself, but for anyone else experiencing this issue.

I tried 4 different phone numbers: 3 of them real, and 555-555-5555 for a screenshot to post on the forum. While possibly area code 555 may be hardcoded as invalid, the other 3 were real mobile phone numbers belonging to myself and family members.

I was already on latest version (3.62.0.3146) of Cox app, and uninstalled and reinstalled, and same issue. 

I'm on a Pixel 3a, Android 12, running the last version of Android available on this device.

Service Rep Nancy said she would make a note on my account, she couldn't give a ticket number, but said her team was working on it, and if it was not resolved in 72 hours to call back. However, the next time I'll be able to try inputting a phone number for outage alerts is the next outage they know about. So it may (hopefully!) be a while. 

Please send this to the app team to investigate and resolve this issue with inputting a valid phone number in "Sign Up for Text Notifications" in the Customer Trending widget. Thank you.