Can not send emails

Level 3

My email stopped being able to send emails yesterday the 2nd March 

I can receive emails but can not send on either my mail platform on iPad or on webmail.

why is this? It comes up sender address is invalid. I have changed passwords as well but still no good.

Level 5

It seems that the error is due to recipient 's email. Have you tried to use their post office to send an email? If it works, then you may need to reset your TPG password as advised on this thread

Level 3

Yes done the password reset, had tech on phone as well and they are still trying to figure it out as well after trying many things. As email can be sent on webmail, but not form my mailing thing on iPad 

Level 2