Your social media account could be your account at Facebook, Twitter, Instagram, LinkedIn and others.
If you think your account was hacked, then there are several things you can do. Usually if your account was hacked then weird things or things you would never post start turning up as posted by you. They could also start changing settings and also sending things to people you have as friends, etc. on the account.
If another account appears as you it is from spoofing and very unlikely you were hacked. In Facebook you see this happen often and iit is just someone created another account with your name and looked in your account and found the list of friends and put them as friend requests from your new account. They really have no access to your account but there used to be a way they could get in your friendsí accounts from here. However, Facebook has been saying for a while that hole was patched. If you get a friend request from someone you thought you were already friends with, wait a day or two and see if request disappears (in Messenger of Facebook). I have found Facebook detects and removes these spoof accounts regularly and catches almost all. Then when you look at requests a day or two later it is gone. There is also an option on a page to report it looking like a fake.
If you think your account was hacked, then the first thing to do is to change the password. If you change the password, then they no longer know your password and cannot get in. Like if you lose your house keys and if you have locks re-keyed, someone finding your keys cannot get in your house.
If you are blocked out, then try the lost password link and hopefully they did not either change the security question/answers or the SMS (text) phone number and you can change the password from what they changed it to. It is helpful to have your cell phone number at these locations so they can contact and send a verification when password changes done, and you can still get in.
If you had two factor authentication on they would not be able to get in your account with just the password, but would need your phone to read code that is sent from, or your finger if using finger prints.
I have received texts from Facebook sending the link to change my password when I had not changed it and that told me someone was trying to hack my account, but I ignored as I had not made request and they hacker was stopped at that point.