Spectrum/TWC/Charter outgoing emails on AT&T network (not wifi) not working
This is an answer, not a question. All the chats on this topic were stale so I had to pose a new question to post this answer. I had the same problem that many have stated they have on Apple Communities and AT&T Community Forum. That is, you can receive Spectrum/TWC/Charter emails on your iPhone while operating on the AT&T network but can't send. You can send and receive on wifi. The usual answers are that you need to check your email server configuration or it's an AT&T issue or it's a Spectrum/Charter issue or that your email has been blacklisted. In my case it was something far simpler. I have an SE 2 operating on 14.4 and Roadrunner email through Spectrum with AT&T as my network carrier. In Settings/Mail/Accounts/my email account/Account/ there are sections for the incoming and outgoing mail servers. The outgoing is collapsed when you open that page. Open outgoing. Open the primary server. Check the password! Spectrum fails my password randomly about once a month and I have to update it on my desktop and phone. Apparently I had updated the incoming email server pw but had failed to update the outgoing server pw on my iPhone. One would have thought they would automatically be the same, but that's not the case. So if you have an issue where you can receive but not send email when on a network only (AT&T, Verizon, whatever), check that both your incoming and outgoing server passwords are correct. Hopefully this helps someone and is just not a blinding flash of the obvious.