Data discrepancy - Mongodb cloud data

Their is a disconnection between question asked in Quiz and database data.

Example: What is the value type of the ts field for documents in the collection?

There is not ts field in data collection, Am I missing anything, Anyone else having same issue?
This is not the only issue - In Video db --> Movie collection having similar issue.

Username: m001-student
Password: m001-mongodb-basics
Replica Set Name: Cluster0-shard-0
Read Preference: Primary Preferred

Not every document has a ts field but it definitely $exists:

Hi @dotnetguts,

In addition to @007_jb,

Please use the Schema Tab in Compass for solving this kind of quizzes and labs. All the labs and quizzes are consistent with the current state of the dataset that we have in the class atlas cluster.

Please let me know if you have any other questions.

Shubham Ranjan
Curriculum Services Engineer