How to have additional information input field for claim submission

How to have additional information input field for claim submission

Example :
Require a new field <Merchant Name> for employees to enter the information when submitting new claim.  

Solution:
1. Go to Expense > Expense group/type.
2. Go to the claim item and setup the additional field

3. Enter  "Merchant Name" in <Name> field and tick the check box <On/off> and <Compulsory> if this is a mandatory field