I am currently employed and holding a 401K with my employer. I need to withdraw the funds to pay off unsecured debt. My employer says I cant do that

The terms of your employer's 401(k) plan are set fortuit plan document. That document alone determines your right to withdraw funds from your individual account while you are still employed. You must refer to the terms of the plan document, and an attorney cannot assist you in obtaining a withdrawal if the plan does not permit it.