Delhivery — Wrong amount charged for the parcel weight

I ordered for 2 waybills. One to bangalore and other to kolkata. One of them
Only had 3 glass bottles. Their weight were less than 500 gm.
In the dashboard i could see the weight mentioned as 995 gm and the amount charged was 90.86.
How can you justify extra 400-500 gm.
For the other parcel had only 2 pair of slippers whose weight was again less than 500 gm.
In the dashboard the weight shown was 1344 and amount charged as 138.06 miles.
From where can i get the weight measurement of my product. Was the measurement done correctly??
How can we reconcile the weight as both the measured weights were different.
Please let me know.