How to add the data into properties.additionalData inside Threat Intelligence Indicator ?

Question

I have created a Threat Intelligence Indicator in Microsoft Sentinel using this REST API ["https://learn.microsoft.com/en-us/rest/api/securityinsights/preview/threat-intelligence-indicator/create-indicator?tabs=HTTP"] and indicator was created successfully into Microsoft Sentinel Threat Intelligence .

But somehow I am not able to add the data in "properties.additionalData" which is present in "https://learn.microsoft.com/en-us/rest/api/securityinsights/preview/threat-intelligence-indicator/create-indicator?tabs=HTTP#threatintelligenceindicatormodel".

Can someone let me know how to add the data into "properties.additionalData" or how to update it ?