As announced by Bitfinex team:
We have recently been made aware of a fake Bitfinex tech support phone number circulating on the Internet.
The individuals behind this number claim an association with Bitfinex. They are committing fraud, and there is no such association with us. They will try to obtain information from you about your account, either by having you disclose your password directly on the phone or by asking you to install software on your computer that will be used to gain remote access to your computer. Once they have enough information to access your Bitfinex account, they will withdraw the funds from your wallets. This has, unfortunately, happened to a number of our customers. We are coordinating with law enforcement.
We do not have a phone number for support at this time. Bitfinex will never ask for your password or ask you to install any software on your computer to provide support.
It is vital that you do the utmost to maintain the security of your Bitfinex account. Be skeptical of any information you are provided and exercise caution when dealing with anyone, even if they claim to work for Bitfinex.
Separate from the above recommendations, we advise that you enable the recommended security features on your Bitfinex account. These features are especially relevant in these times and can be learned about in greater detail below:
The Bitfinex Team