I have a voucher from AF from last year that is about to expire at the end of 2021. The rule says it can be applied to Delta flights too.

My original plan was to book a short US domestic flight, but the voucher did not work on Delta's website. I contacted both Delta and AF, and was told that I must book from AF's website.

What they didn't tell me, it appears, is that Delta's domestic flights are not listed from AF's website. In fact there appears to be no US domestic flights on AF's website.

Has anyone run into this problem before? What are my options? Thanks in advance.