C++ kiteconnect getInstrument() throws libException

I am able to generate session and fetch margins and LTP/Quote. But when I try to fetch instruments using the following code, I am getting an exception:

	
std::vector<kc::instrument> inst = kiteObj->getInstruments(kiteconnect::EXCHANGE_NFO);
	for (auto const& i : inst) {
		std::cout << "symbol: " << i.tradingsymbol
				<< " token: " << i.instrumentToken << '\n';
	};

The exception is :


The API seems to fetch fine probably fails when it tries to format the string.