Why are IAS toppers of India are not able to speak Indian national language 'Hindi' correctly ?

Three top IAS rank holders of recently declared civil services examination conducted by Union Public Service commission(UPSC) of India, all women, were interviewed by Indian TV news channels in Indian national language Hindi. All answered well in details but none of them was able to speak correctly in Hindi. The top ranker Smt. Shubra Saxena, while answering a question said, "Mere ko maloom hai ki kya karna hai." She should have said MUJH KO instead of 'mere ko'. She belongs to Ghaziababd of UP, the hindi heartland. The third ranker from Raipur, MP, said, " Taiyari kaise karna hota hai" instead of "Taiyari kaise karni hoti hai". She too belong to a state of Hindi language. The second ranker is from Punjab has mother tongu Punjabi & so was worse in speaking Hindi. This is the condition of so called top bureaucrates of India. Can't UPSC do something to improve the standard ?