NimbusPost Pvt Ltd - Repeated False Weight Discrepency

I recently started using Nimbuspost. starting orders were going smooth then they started to charge extra on each shipment in the name of weight discrepency. They charge for **kg shipping amount while the real product and volumetric weight was only *kg. They are eating our hard earned money in the name of weight discrepency and they dont solve the queries and say send picture of the product with proper dimension which is not possible for already delivered products. Till now we have lost around *-* thousand rupees due to this and mental harrasement