I don't know if this is T-Mobile's problem or Spectrum, but I cannot get outgoing mail to work on my Android when connected to T-Mobile cellular data. Works OK if my Android is on WiFi.
Security protocol: TLS
Mail client says server did not respond when using above.
Server rejects connection to port 25 with "service unavailable"
I had used mail.twc.com, same problem.
Inbound mail with imap not a problem
Best answer by tmo_laurenView original