Need to Disable (Non Editable) Field "UNIT_PRICE" on Invoice Matching Form

On :  12.2.4 version, Invoice Issues Requirement is to  disable a field UNIT_PRICE, where we are matching a invoice to receipt. Currently UNIT_PRICE is enterable field and we can change the UNIT_PRICE once we match receipt. Kindly correct as my Requirement is to have UNIT_PRICE field need to disable (Non Enterable Non Editable). it should be greyed out. My Personalization Code is as below. **************************************************************                  Condition ************** ************************ 1. Trigger Event: WHEN-NEW-RECORD-INSTANCE (Changed This value)  2. Trigger Object: RECEIPT_MATCH 3. Trigger Object: nil  4. Condition: nil  5. Processing Mode: Not in Enter-Query Mode  6: Level = Site              Actions ******************************************  7. Seq = 1  8. Type = Property  9. Description: Disable Price  10. Language: All  11. Enabled: Yes