Seamonkey mail not arriving from ATT.Yahoo.

Seamonkey mail not arriving from ATT.Yahoo. Windows 7
About 10 days ago (am) all was fine. A few hours later Seamonkey POP mail was not arriving from ATT.Yahoo. Mail was not at Yahoo for several days. Then it began showing up but was not being transferred to SM.

Changed passwords in ATT and Yahoo. Nothing. KEEPS ASKING FOR PASSWORD TO SEND AND RECEIVE.

Installed Thunderbird to use it for SM mail. Some old mail loaded. Several months worth did not. CANNOT RECEIVE OR SEND MAIL. KEEPS ASKING FOR PASSWORD TO RECEIVE AND SEND.

Installed SM in Chrome thinking that might help. NOTHING. Same problem

PASSWORDS ARE CORRECT.

Thanks

 

Are the POP and SMTP numbers right?