Yes its scam because i am verifed member, and they not replied to me after i send selfie, 4 days passed.
That doesn't make it a scam... that is Poloniex having poor support and customer service
If they just instablocked your account and confiscated all your coins without a valid reason,
that would be a scam.
Most likely, something has happened that has triggered the security block on your account... trading from a different geographical location, account waking up after a period of inactivity and suddenly withdrawing a large amount, multiple logins from various locations, unusual account activity etc.
Them asking for a selfie, is probably them trying to match to your original "verified" documents... to confirm that the person withdrawing coins is the legitimate owner of the account. That sort of thing requires manual review and verification, which requires time.
Granted 4 days is pretty unacceptable, but then, Poloniex
is renowned for having terrible wait times for support requests.