The rules of selling accounts that are linked to Facebook

[PinkyBlossom]

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Currently, I am selling some accounts of TapTap Heroes mobile game, and there are two forms of linking accounts of this game, Gmail and Facebook, and can't unlink.
Can I get some more information on this issue to avoid breaking the rules of epicnpc?
This is the attached image, I don't really understand the 3rd answer

 

[Master-Trader]

WARNING! Off-site contact information posted. We do not investigate disputes if you communicate off-site.

It says;
in case of the account is linked to facebook account and you are not able to unlink it, when someone else logins for first time, Facebook account may get locked.
That's all

 

[doomedtofail]

WARNING! Off-site contact information posted. We do not investigate disputes if you communicate off-site.

It happens a lot with fake facebooks. facebook typically asks you to verify information to login like posts and other things like friends. if the facebook is fake there is not way to answer those questions and unlock account. Other times it just gets banned.

 

[PinkyBlossom]

It happens a lot with fake facebooks. facebook typically asks you to verify information to login like posts and other things like friends. if the facebook is fake there is not way to answer those questions and unlock account. Other times it just gets banned.

Ty so much!