3571829 - "You are not allowed to modify the standard field" Error Due to External Post Hook Execution

You may encounter following errors when attempting to modify certain attributes of an instance. 

• Error: Error while parsing response data for post-hook external hook in XYZ. Contact your administrator with log ID

By navigating to the Extensibility Administration and checking errors log, you can see the following error:

• You are not allowed to modify the standard field "ABC" under the instance path "" in external postHook.

• SAP Sales Cloud Version 2
• SAP Service Cloud Version 2

Error: Error while parsing response data for post-hook external hook, Contact your administrator with log ID, You are not allowed to modify the standard field, under the instance path "" in external postHook, external hook, error, extensibility administration, configuration, Error while parsing response data , KBA , CEC-CRM-CZM-CUL , Custom Logic for for SAP Sales/Service Cloud , Known Error