dataprep load error on Qlik Sense

[brian1]

I'm seeing an error when trying to access the Data tab for a Qlik Sense app:
The error is a 500 response for the following URLs that are loaded when I navigate to the data manager:

https://my-company.us.qlikcloud.com/api/dataprepservice/v1/apps/1234v4d3-e17a-rs35-rsd4-fj4985687f38...
and 
https://my-company.us.qlikcloud.com/api/dataprepservice/v1/apps/hr5g4g5-544g-grtg54-gtrg45-grregerge...

The error response for both of these requests is:

{"error":"Invalid dataprep model: {0}"}

Is anyone familiar with this error message?

[Anil_Babu_Samineni]

IS that source is password secure?