iterator problems

auto& slaveiter = slave->listOfDailyStock.begin();
std::advance(slaveiter, 1);

Severity    Code    Description Project File    Line    Suppression State
Error   C2678   binary '+=': no operator found which takes a left-hand operand of type 'const std::_Vector_iterator<std::_Vector_val<std::_Simple_types<dailyStock>>>' (or there is no acceptable conversion)   AP_Exam C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\include\xutility 1084