Direct Cost booking

Dear Friends 

Your suggestion is required 

Suppose we are a manufacturing concern - Purchased Raw Material at Rs 100 and conversion cost and other direct cost is rs 80 , Selling Price is Rs 210 

Now the problem is we forgot to book conversion cost and direct cost associated with this particular purchase and sold the finished goods at Rs 210 

Now Margin is 210-100 =110 instead of 210-100-80 =30 

Please suggest what adjustments can we make Now when that finished goods is sold without being added direct cost associated with it 

We maintain books in Tally Prime 

Urgent please help