selling youtube channels with security errors so u cant do amything with it [Resolved]

I bought youtube channel from him today at 9 am
when i opened it to check right away as he told me, without changing password or any security majors, i found that many features of it are blocked because of security problem
I told him to fix it, he told me to change adsesne to another he gave me however i could not even go to associated adsense point where u change adsense, which shows he tries to say anything after awhile he told me it is youtube update
then he refused help to fix it, replacement or refund
He was once a good seller now if u buy from him, you lose your money forever.

[Resolved] Received a partial refund