Hey there,
Only few people that frequent these Forums have access to drops, so sorry for the late response!
Looking at it from the outside, a guess i can make would be: Check if the viewer that claimed the Drop still has the App (aka Client ID) linked to their account. They can check on their Connections Settings Page.
I may toy with some drops today or so, so if i notice any other bumps in the road you may be stumbling on, I’ll come back here!
Cheers