These unknown alleged Exchanges tend to be part of a family of such, likely based on common website skeletons, with some individual tweaks here and there. These sites for example have the same wording describing their “Products and Services”:
https[colon]//www[dot]nexinter[dot]com/en_US/
https[colon]//www[dot]wbfex[dot]one
https[colon]//www[dot]bi[dot]cc
https[colon]//www[dot]indomex[dot]com/en_US/
The modus operandi is rather well known: High yields, perhaps allowing for a quick first withdrawal, request further and larger investments, demand more to allegedly enable any more withdrawals with some bogus pretext (i.e. taxes, minimums, etc.), and so forth.
By the way, if you happen to have downloaded and installed their app, you’d better look into it, as it could easily be a backdoor to having installed spyware, RAT or such type of malware on your mobile device.