Signed a freelancing contract with a company that doesn't answer my inquiries anymore.

Hello everybody, Ive recently signed a freelancing contract with a company called Olympus IQ, which according to LinkedIn, the headquarters are in Texas, but they also have an alleged branch in Portugal, Lisbon. The thing is that their HR specialist doesn't answer my emails anymore, and it is worrying me, since I've provided my home address and number of my passport, as well as my social security and fiscal numbers. I am situated in Portugal (if that helps) Does anyone have any information about this company? And what do you think they can do with my details in case this company is a fraud? Thank you for the help.