https://help.tallysolutions.com/docs/te9rel60/Creating_Masters/Inventory_Info/Altering_a_Stock_Item.htm

Altering a Stock Item

This option allows you to view and change the details for the existing Single Stock Item master and Multiple Stock Item masters. If a transaction is entered for a stock item, it is not possible to alter the units or delete the stock item.

To Alter a Single Stock Item

1.    Go to Gateway of Tally > Inventory Info. > Stock Items > Alter (Single Stock Item).

2.    Select the required Stock Item from the List of Items. The Stock Item Alteration screen appears as shown below:

3.    Press Ctrl+A to accept.

To alter Multiple Stock Items

1.    Go to Gateway of Tally > Inventory Info. > Stock Items > Alter (Multiple Stock Items).

2.    Select a stock group from the List of Groups to alter the stock item under the selected group or under All Items. The Multi Stock Item Alteration screen appears as shown below:

Note: In the Multi Stock Item Alteration screen, you can create an item by entering the item name after the last item, but you cannot delete an item.