I have yahoo mail and I cannot access my account. I get an error message. Yhoo seems unable to solve this?

I get an error message. I can access one account but my main account is inaccessible. Yahoo help has been totally unsuccessful. Does anyone have suggestions as to how I may rectify the problem. Yahoo is unreachable except for on line help which has been useless. All my information stored under my main e-mail account has been totally unsuccessful.