The “Voucher Number Already Exist” message appears when a voucher with the same number is already saved in the system. Each voucher number must be unique to prevent duplication. This issue can occur if the voucher series or numbering is not properly configured, or if an earlier voucher was created with the same number.

To resolve this, check:

• Whether a voucher with the same number already exists.

• The voucher series configuration to ensure automatic numbering is enabled or properly set.