Did you use a free VPN when playing on FJ? If you use a free VPN then the IP might be used by other person and you are suspected to have multi accounts. Indeed FJ should give you more proofs about which accounts is connected with yours, but to be honest I dont think that FJ will scam their players just for that small amount of coins.
Nah. It seems these casino sites detect you using a vpn by seeing if it is a throttled connection you have.
This is probably how other sites can detect you using one and they just block you if you try to do a withdrawal saying you are doing that cause you have something to hide.