Unable to connect to Comcast email from Android (stopped working)

I am unable to consistently connect to Comcast email from Android Outlook app. This app has been working fine until recently. About a week ago, I received an error that I needed to re-enter my password. I did that, but it didn't help. I deleted the account from the app and tried to re-add it. That failed. However, about 12 hours later, I tried again and it worked! Then two days later the same thing happened. Today, yet again, it has stopped working. Here are some relevant facts,

  - I am only having this issue with my Comcast email accounts.

 - Outlook connecting to my Comcast accounts is working fine on other (non-Android) devices.

 - Yes, I know my Comcast account password!

 - I deleted the account from the Outlook app, cleared the app cache, rebooted the phone,  but it still won't add the account (login errror).

- It seems that after 12-24 hours (based on previous experience) it will allow me to add the account; and that after 1-3 days it will stop working again.

- I have more than one Comcast email account set up in my Outlook app. Currently, one is working, one is not. Which one is not working varies.

- I am using IMAP. Yes, the settings are correct!

- I am an IT professional and this isn't (shouldn't) be rocket science. Yet, here I am.

- No, I am not going to wipe my phone and start from scratch. Every other email provider is working fine, this is restricted to Comcast only.

- I had a similar problem with Comcast accounts about a year ago, but it went away.