Download link for virtual products in emails are broken

Hello!
I’m creating a shop for books and ebooks. It’s not necessary to have a account to download the ebooks. But the download-link in the woocommerce emails are broken.

I found out that the &-operator of the url-varible is missing:
Generatet URL by woocommerce:
http://my-website.de/?download_file=4585order=wc_order_530e585a3634eemail=name@gmail.comkey=e1502a13011c35adb48cb8a7eb4a33a7

But the correct URL should be:
http://my-website.de/?download_file=4585&order=wc_order_530e585a3634e&email=name@gmail.com&key=e1502a13011c35adb48cb8a7eb4a33a7

Could you help me to fix this urgent problem?

https://wordpress.org/plugins/woocommerce/