Why can't I Send An Email From My Galaxy J3V?

Question

I'm using yahoo email perfectly well on my S5 and my daughter's S7 but my wife's J3V will only receive emails and not send them. The error is : Unable to send email

Error occurred on email server. -

530 5.7.1 Authentication required

Please help

MASSIJC · Accepted Answer

I solved it myself. The telephone number of the device I was using was not listed in the yahoo settings. Once I added and authenticated the device phone number......authentication solved and emails sent.