@AbhishekS7581  This issue might occur due to several reasons. One possibility is that the properties are not marked as relevant records, which can cause them to be missing when you export the data model. Another possibility is that the properties are not being populated for newly exposed columns. If you have recently migrated code, it's also possible that the properties are not visible in the data model after the migration. You might need to check these aspects to resolve the issue.

1. **Property Names as Labels**: The import file only accepts property names as labels, which might differ from what the business expects. Ensure that the labels in your export file match the property names exactly. 

2. **Data Model Visibility**: If properties are not visible under the data model, check if the 'Show Inherited' filter is applied. Sometimes properties created at the same level might not be visible without this filter.

3. **Code Migration Issues**: If properties are not appearing in the data model after a code migration, ensure that no changes were made to the 'pyDefaultReport' of the data class. Reverting any changes might resolve the issue.

4. **Property Type Changes**: If you have changed the property type, ensure that you have exported or downloaded all records before making the change, as existing records will be deleted.

Issues with Import CSV file 

Data Model Tab of Data Type 

Code Migration - Properties are not in Data Model

Not able to change column data type 

Missing columns in Explore Data > Cause: Properties not marked as relevant records

Values not populating for newly exposed columns