Need some genuine help regarding Indiapost

Hello guys! I need some genuine advice from delhites regarding this issue with Indiapost. I posted an international Speedpost from Chanakyapuri PO to USA, on 27th May. I have sent parcels to USA in the past as well and they have consistently reached in a week or 10 days at max. Speedpost is a time bound service and they claim 4-7 days of delivery time. However, today is 14th of June and last update on the parcel was on 29th May of it being accepted in a flight. Nothing more. I suspect its lost or idk whats up with it. I have lodged a complaint online, called them multiple times, tagged them on twitter, mailed to Delhi speedpost grievance head, nothing has helped. Does anyone know how i can proceed further? Parcel had an expensive item. Any leads would be appreciated. Thank you!