Steam profile linked with other account

Hello. So at some point probably years ago I linked my Steam account to a different account from this one. This one I am using now is the one I want to link with. Is there any way we can get that other account deleted or even just unlink my Steam account so I can add it to this one, which I set up with the premium membership? Any help would be appreciated or tell me who I need to contact. Thanks. 

If you use steam to login you will access the other account. Then just unlink it from your account at this url: https://sortitoutsi.net/account/social