Sufficient Traveller's Fund for Nigeria

is there a such thing as Sufficient Traveller's Fund fee to have on you to be able to leave nigeria. A supposed girlfriend has told me she has to have a required amount on her for safe travel from nigeria to the USA called Sufficient Traveller's Fund. She got me email from embassy and the guy wrote back that she does. I have also emailed on my own other places and got replys also stating you have to be able to show 6 months of accounts or statements assuring you can be able to leave the country of nigeria. SHe told me she was working for unicef being down there until we have been talking for quite sometime and wanted to come see me instead of following unicef. I sent her some money to finish flight ticket which she sent me copy of electronic ticket purchase online. then proceeded to say she still had to see immigation before leaving nigeria. was told to hold on her person Sufficient Traveller's Fund this is a token sum of amount that She must have on her before she can be allowed to leave the shore of the Country there, This fee is not to be spent or paid to anyone, it is just to be shown to the Nigerian Immigration at the airport that she won't get stranded when she get to the stage of departure and incase of emergency use. I have looked up her flight booking number on actual airlines website and it does show up as true. curious is anyone knows of this and replys would be helpful. thank you