Shipping Charges is summed up instead of individual values

Upon exporting Order Items, with WCFM multivendor plugin, column J has shipping charges summed up in each line of same order. for Example, Same Order ID has 2 lines, each line has different vendor with different shipping charges. But on export of Order items, each line is found to be Sum of value of both lines. Can it be obtained properly ? Instead of showing shipping charges for Line1 = 15, Line 2= 20, it exported Line1= 35, Line2= 35