How do I reset which Facebook profile is linked to my iPhone?

[Technogood]

Eg. My husbands Facebook account automatically appears on my iPhone 6SPlus when I want to post a utube video to my Facebook!

 

[Just_Me_D]

Sing out of Facebook on your iPhone and then sign in using "your" Facebook credentials.

 

[kataran]

Welcome to iMore

If your using the Facebook app then your husband is signed into the Facebook.com which YouTube is trying to connect with on the web. Sign out of the web page and sign in with your account as mentioned above