I am sending gmail to my ex employer at the mail id indicated by them. The response which I am getting from Postmaster is that 'The recipient weren't found at XXXX address'. I am sending mail to 'A' and the message is indicating that mails are not able to reach 'B' & 'C' because 'The recipient weren't found at XXXX address'. There is no response from 'A' either.
And, of late, they are claiming that no mail is received from my end.