My email password did not work , so I changed it , however it opened but in another username..? Can anyone help .. I have online PC support tech but they wer useless… Im begging

Hi there ..I opened my email this morning , but my password did not work (triple checked) .. So I changed it via security question however when I entered the new one the window opened but the user name is different and it has one email from Outlook (welcome) as if it is a new account . I have online PC support however the tech gave no answers  other than we can configure the email for security , they also stated that I deleted all my OWN emails (born yesterday)..    I'm am  exausted with frustration ... Can anyone help Please !! Super please