Accounting Date Freeze in Regular Entry

Hi,

There are 3 payments in a voucher. 1 is for vendor payment and other 2 are WHT for the vendor. The WHT has been paid however the Regular Payment hasn't been recorded. Now, when we are going to record a payment in Regular Entry for that voucher. It says Accounting Date cannot be empty; however, the accounting date field is freeze in Regular Entry for that line. What is the solution? As we cannot delete or close that voucher because 2 payments have already been made.

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