I have been scammed 6 months ago
Then criminals expect you to be gullible and foolish. You are a prime target for them. So they'll try new ways to trick you.
BTC REFUND DEPARTMENT
No such thing.
synchronise my wallet with the address
They want to fool you with a watch-only address, where your wallet shows an amount of money that belongs to someone else not to you. Addresses are not secret. Anyone can add any bitcoin address to their wallet but that doesn't give you any control over money.
Bitcoin wallets do not actually contain money. Wallets contain a secret number called a private-key that a wallet can use to control money. Importing an address doesn't give your wallet this secret number.
the amount is under my name
That's not how bitcoin works.
Some businesses that sell bitcoin might ask buyers to set up a named account but that's outside the real Bitcoin system.
hi is asking 10% of the amount to be added
This is often called "advance fee fraud". Don't be tricked. There is never a need to pay any fee to release money. If there were, it could just be deducted from the amount being returned, you wouldn't have to pay it first. This is a favourite trick of confidence tricksters.
Is this true or is just another scammer
It's not true. It is just another scam.
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