What privilege is required to update the payment descriptive flexfields? (At Manage Payment)

Summary:

At Manage Payment, under general information, we have created 2 disbursement flexfields.

For exactly same payment and same UI, We spot that user 1 can edit the input in those fields. User 2 cannot edit the input, only view allowed.

May I know what is the priviledge required to be able to edit the flexfields?

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