E mail fault

Hi I’m having an email problem. I have an iPad and iPhone neither of which are receiving emails the I pad since two days ago the iPhone today at 1.30.At this time I was dealing with BT over a change of telephone which may have some significance! I can’t send emails either and a message in the outbox where they are residing is

“Cannot send mail

The username or password for

“*****@mail.btinternet.com”

is incorrect

Iam sure this is a glitch as I have changed nothing and internet is OK

I am sure there must be somebody out there with some ideas- help!

Sonia

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