ANSWER:

These are the traps of Shaytan to drag your feet into hell. Don’t look at the size of the sin, look at Whom you are sinning against! It is not permissible for a woman to work or study in a mixed environment. 

QUESTION: Does often free mixing turn into major sin? For example, as a woman I am trying to limit free mixing especially at work but fall in it at times so what erases it do I need to ask for forgiveness every time or which acts erase it?