NIC for dependant on skilled worker visa

Hello! I'm on skilled worker visa currently and my wife is on the dependant visa. Our visas sponsored by my employer. My wife has found a job here in UK. She sees NIC deducted from her salary in the payslip. Should she really pay NIC? I believe this is paid by my employer as he is sponsoring us. Is it correct? What should be done to avoid this deductions in future? How my wife can apply for the refund?

Hi 
As your wife is working in the UK then she will be liable to pay National Insurance.
Any questions regarding your visa should be discussed with your employer or with the Home Office.
Thank you.