India Post — About my parcel from India to New Zealand

We had sent an parcel of weight 17700 gram and also paid 9390/- to post office(CP[protected]IN) its been 51 days that my parcel not reaches at Newzealand, its stuck at IGI TMO New Delhi, i use to mail everyday to them but they also replied as UR ARTICLE IN TRANSIT, if my article actual in transit then it should be reached at destination country till now, they are just trying to bug me off, its my niece's first b'day on 25 jan, we didn't met her till now because of lockdown but we had send lot of items for her special day as our love and blessing, it was out biggest mistake ever to trust on India Post service, only 3 days are left in her b'day, its my humble request please help us to sort it out