Shipment cost Recalculation not working for modified values

Hello All,

I have been facing a peculiar issue in shipment 'Recalculate cost' option.
My rate is based on Order total declared value. At time of order creation, I am posting a value on Order line declared value. Rate cost is based on declared value. At time of shipment creation, planned rate is correct. But when i try to modify the Declared value and recalculate shipment cost, the cost remains unchanged.

I have checked all values in Order_release and Order_release_line tables, The value are modified in both the tables but the shipment recalculation does not consider the modification.

Please advice as this seems to be a very weird issue.

Note :: I tried recalculation based on weight and volume. OTM works fine in such cases.

TIA
Snigdha