Hello,
Sorry for the delay. The error message was hidden deep, but it turns out that DaReUS-Loop cannot find any sequences with a close enough sequence profile (Jensen-Shannon score better than 0.4) . We will update the server in the coming weeks to give a clearer error message. I regret that DaReUS-Loop is not able to handle your protein.
best
Sjoerd
[ marking the issue as “Solved”, because there is nothing else that can be done, unfortunately ]