Able to receive emails on the iOS native mail app setup for Yahoo! Account but not able to send out emails. Keep receiving error message on wrong login or password etc.
Tried manual setting but still have the same issue.
How I solve it:
Turn on less secure access to your Yahoo account by clicking here:
https://login.yahoo.com/account/security#other-apps and turning on ‘Allow apps that use less secure sign-in’.
If you are concerned of security breach then you may not want to try this approach. However, for a quick fix you can use this method and then turn it off after you sent out your emails.
Hope Apple have a fix for this soon. Alternatively is to download Yahoo mail app and use that to manage your yahoo account.