College students in the school and home have paid for health insurance, duplicate enrollment, what will happen, what is the impact?

Hello, the college students in the school and home to pay the medical insurance, repeat enrollment, how will, what is the impact? In other words, the commercial health insurance will not reimburse the insured for what is already covered by social security. If there is a deductible included in the commercial insurance policy, it is necessary for the insured person to exceed the current coverage of the deductible before the reimbursement can begin to accumulate.