employment during waiting for OPT due to payroll system didn't terminate my account in time

[jiaer]

Hello, I received completion letter on May 31,and shouldn't be in employment until I got my OPT. I kept working as volunteer in my lab after May 31,but the department missed the email from international students service's letter with my name on the graduation list, so they didn't terminate my payment account. On June 13, they pay money to my bank account. One week later, when I brought my new I-20 to payroll office to renew, the officer in my department payroll found the date is changed to May 31 on my new I-20, they called ISS, and they said I have to stop working immediately and had to terminate my F-1, thus I had to go back to my country. I was willing to return the money but they didn't accept. I argued with ISS officer these days, and collected evidence from lab to prove that we already made aggrement that I only work as volunteer after May 31. But ISS just want to submit this issue and terminate my F-1. Apparently, it's not all my fault to get the payment resulting in my violation of the law, what should I do to let them not terminate my F-1. Because my OPT application fee has been accepted and processed. And I will be hired in the lab after I got my OPT.

My university is in Texas. I have got whole support from boss and coleagues in the lab, they all proved me as volunteer after May 31. But because I submit timesheet as a habit, the payroll approved it and resulted in my payment on June 13, ISS just didn't care my future and the fault of payroll system who didn't terminate my account in time. They just want to terminate my F-1 and let me leave US immediately.

[marywilson]

Several kinds of work count as "employment" while on your original 12-month post-completion OPT, but it must be at least 20 hours per week and related to your degree program to count.

Paid employment for one or multiple employers (all must be related to your degree program).
Self-employment, if you start your own business, have the proper business licenses, and are actively engaged in a business related to your degree program. You must be very careful to document full-time work.
Employment through an agency
Unpaid (volunteer) employment as interns or volunteers provided this does not violate any labor laws. Your "employer" must provide evidence that you worked at least 20 hours per week during the period of employment.
Work for hire - that is, work you do based on a contract rather than an employment relationship.