You have upgraded your Development instance to NY patch 1 - Hot Fix 1. You have reverted all the customizations related to the on-call back to OOB, so we can be aligned with the ServiceNow code base and also utilize all the features and advancement that have been made on the new On-Call as part of NY release. We have encountered below error as we begin the testing after reversion.
Expected argument of type object, but instead had type undefined
Steps to reproduce:
1. Navigate to the On-Call schedule application
2. Click on Create /Edit Schedule
3. Pick a group, fill the fields and click next
4. You'll receive the error message and you can't make any further steps.
Issue has been caused by heavily customized file below
This file is not at the upgrade version but rather has been merged with your customizations.
I will suggest you revert the following file back to the upgrade version
Reverting this file fixes the issue.