my mailbox cant sent or receive emails

Yesterday I tried to login to my mail via https://currently.att.yahoo.com/ from Chrome on my laptop. The Sign in link no longer works. I am connected to the internet and can reach other pages. Access to my mail from my phone works as usual. I have received numerous emails over the past few months pu

When attempting to login to my AT&T email account on iPhone 15, I get a message "We've detected a SIM card change. Select Try another way to use a different mobile number". I am getting the 6-digit verficiation code sent to my phone through text, but get the message.  I have gone into my a

Several of us use att.net to SMS and MMS texts. In the last couple of weeks they began to take longer and longer to arrive. Now they don't arrive at all. We have tried different PC's at different locations and different phones. No error messages are created and the messages are never received. All