Parser error

[carculator]

I´m lost. This seems to bee perfectly fine, but throws:

    auto js =  "{"title_prefix": null, "firstname" : "Jane", "Lastname" : " Doo","street" : "Placa 1","zip" : "92912","city" : "Somewhere","country" : "US"}";
    auto j = nlohmann::json::parse(js);

[json.exception.parse_error.101] parse error at line 1, column 6: syntax error while parsing value - invalid literal; last read: '"{"ti'; expected end of input

Any hints are welcome !