Sorry to hear you got scammed, luckily at least you got your deposit back.
I really think once you go above a 5 figure sum for a deposit, you really got to choose your brokerage extremely carefully. I do not see from the website of primefms exactly where they are based, when I Googled all I found was bad news, and on one such site I found this;
The domain primefms.com is privately registered via Domains by Proxy - No legitimate ownership details are publicly visible on Who.Is. Companies with little to no transparency are usually hiding something.
The website is hosted in Moscow, Russia or they are disguising their location by using a proxy server in Moscow, Russia to route all traffic to their website. Clearly these guys are trying to cover their tracks.
Their domain is very young - less than 110 days old. They also have no reputation on goggle despite their website and support staff claiming "They are one of the biggest most reputable Financial Management Service providers" in the industry. Funny how such a "Big Reputable Firm" can have such a little footprint on the web.
Take a look here,
PrimeFMS.com (Red Flags Everywhere!)
I always ask myself why are all the professional traders and prop firms just trade on the Futures markets, one thing for sure is they are heavily regulated and you rarely hear of scams like you do in the retail forex world.