Hello Hitesh,
Just try to change 'Cond.category' in V/06 for your particular condition type. Try by changing it to 'F' or 'L'. lt should redetermine the values however in case if this doesn't work then you need to create new Pricing Requirement Routine (VOFM) and assign the same in VTFL (assuming that in your bussiness process Billing is Delivery-related). The logic of that would be this source code will work only for your Billing Documents by considering their Document category and only it will redetermine the new values of your 2 particular condition types else for all other condition types, discounts/surcharges values will be carried as old one. Take the help of your ABAPER to apply the same logic and i'm sure this can help you against your desired query. Thanks and do hit back with your findings.