Periyar University — Regarding refund

My son Sujay shekar Shetty has taken admission in MBA for distance education in marketing in march2022 since he has completed graduation in 2017 he was not eligible for that degree we paid yearly fees after that they are saying he is not eligible since may i am asking refund they are not giving answer also ii have mailed also many times to the university but no response please do the needful and give my refund as soon as possible