Apologies for delayed response.
Could you please share below details with us:
1. The exact values of the parameter you are passing in "findDocumentByQuery" API
2. Complete code snippet of the api call alomg with query creation
Also, please add me(firstname.lastname@example.org) as a collaborator to your app in AppHQ dashboard and share your app name for which you have added me as collaborator.
To add collaborator, go to App Manager -> Collaborator -> Add Collaborator and provide above email address.
It will help us to understand the problem in better way.