I have an iCloud account and there are my phone and a macbook which not belongs to me. I removed it from Apple ID and settings in iCloud, but it is still in Find my iPhone. I only able to erase this macbook. Is there a way to just deatache it from my account without erasing data?
In Find iPhone you should be able to tap on the device you want to remove. That will take you to the screen where you see the
At the top-right of that screen is the option to
Remove that device (see my iPad screenshot below).
Remove option doesn't appear immediately, give it a few minutes to show up. After tapping
Remove you'll get a confirmation dialog box. Once you tap Agree the device will be removed.