Unable to submit the records for the Cutover records uploaded

Steps to reproduce:

1. Login to the S2O portal with valid credentials.
2. Click on Upload button under the switch view from the home screen.
3. Select the process as Cutover and browse a file in proper format.
4. Click on Upload button.
5. Then select the record and click on Submit button.
6. Observe the results.

Expected result:

The user should be able to click on Submit button and S2O Order number has to be generated.

Actual result:

By clicking on the Submit button, the page is loading and nothing records are not getting submitted.