VENDOR / NUMBERS

Hello,
with WooCommerce Voucher, I automated sell vouchers to my customers via. Mail, than they print the them out.

Actually, I want each voucher to have a consecutive number (e.g. it starts at 1000, the next customer gets the number 1001, the next 1002 and so on).

Where can I adjust, where the Plugin begins to assign voucher numbers and where can I adjust, that each voucher continues which Vendor Number by factor +1)

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