US Immigration from China

Hello, I am the petitioner and we have filed our I129f back in July 2019.

We were recently contacted by the Consulate in China with an e-mail and a scheduled interview date. In our case, we did not do the scheduling interview date. The consulate did. The e-mail told us to register online at ustraveldocs.com under "Immigrant Visa - Scheduled by NVC registration only". When we do so, we get to the end and reach the transaction is complete page (seen attached). However, there is no continue forward to payment. There is no payment page available. Has anyone else ever had this situation or can advice on how to proceed further? Thank you.