I woke up this morning with a notification about a trending post on Bitcoin subreddit[1] on How Changelly exchange has refused to release a bitcoin onto user balance,
Exchanges like ChangeNow and Changelley are instant exchanges, even you can make use of their service on noncustododial wallets like Coinomi and Atomic wallet (not recommendimg this wallets as they are close source, not also recommendimg instant exchanges), people are only fooled, thinking they exchange from one coin to another in a way no KYC needed for it. But it happen like this:
The instant exchange will provide you an address that belong to the instant exchange (some people can think it belongs to another person that want to exchange coin too, but not).
You will send the coin you want to exchange to the instant exchange address with the amount you want to exchange. (Take note of this)
The instant exchange will send your the coin you exchange for to another address on your wallet.
You should take note that you send coin to the instant exchange address first before you were sent the coin you exchange to, they have the private key to the address, ones you send your coin to the instant exchange address, the instant exchange can decide to force someone to provide his/her KYC or thy will not send any coin you wanted to exchange to while your coin is already with the instant exchange.
Instant exchanges are centralized, but still better than KYC exchanges that users will have to provide KYC even before making use of the exchange service, which can lead to data breach. But to have privacy, all centralized exchanges be it instant exchange or not are not all recommendable.
Some people can think they are using noncustododial wallet, not knowing that Tether Limited can freeze USDT on noncustododial wallet. Using USDT means someone is not having full privacy because Tether Limited can decide to freeze the coin of any users even on noncustododial wallet.