My yahoo,wasn't this that I never had been using before and i have problems,with my E _ Mails?

Since a month ago,i been losing,my E-Mails.I been tryng to get them,but was impossible.I was been using Ya hoo Clic for 4 o more years,always very good.Suddenly,all my contacts dessapears..But sometimes appears yahoo clic,and is the only way I acn keep intouch with my family and friends