Don't use Interrail to book this reservation. ÖBB (3€ per person and train) or DB (4.5€ per person and journey, with seat selection) are much cheaper than Interrail (8€ per person and train). Use "Seat only”.

I have the same problem. I want to reserve many trains all in one place as I have quite a few and all in different countries… but it’s not working?

The advice from the experienced travellers in the community is to use other ways to make reservations than the Interrail/Eurail website.  You can look at the guide in the link:

https://community.eurail.com/train-connections-reservations-47/how-to-get-reservations-105

If you, after having looked at the guide, have questions about how to make specific reservation, please give your travel details (departure date, time and route) preferably in a new topic, and you will get advice.

Please note that Interrail/Eurail charges an extra fee of 2 EUR per person and ticket in addition to the fee for the seat reservation.

This will be so much harder and time consuming. Is this a permanent problem or will it be fixed soon?

We have seen this issue regularly. What often seems in such a case work is to book each train separately.