unable to edit voucher value

Hi
I have an issue with the gift voucher.
I had a customer who was trying to purchase online and their browser kept freezing prior to going to the stripe payment page
Instead i decided to manually create his voucher
I entered the voucher details and the value into the backend
it shows the record of purchase (great) however it is showing a $0 value for the gift card when it should be $125.
I need to be able to enter manual vouchers (from our previous system) to track values.
How can i do this and still have the value represented in the back end

the screenshot is here
https://www.dropbox.com/s/wct6p8k47gd9gzp/Capture.PNG?dl=0

Please let me know if you need more information

thanks
Ian

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