Can we add the drop-down field for locked system field by using rest API key?

[Jira Admin]

While I am creating ticket. I want to give in" Organizations" Below as "Three UK". It is not in organization drop down field. so, I want to add "three Uk" filed in drop down of organization filed. is it possible to do using with rest API Key?

while I am trying to add Three UK field in drop down of Organizations field using rest API I am getting below error.

{"errorMessages":[],"errors":{"organisation":"Field 'organisation' cannot be set. It is not on the appropriate screen, or unknown."}}

please advice me if we have any feasible ways to do this using with rest api keys

Thank you

[Marc - Devoteam]

Hi @Jira Admin 

Is the field Organisation on the create screen related to the issue type within the project

[Jira Admin]

hi @Marc - Devoteam Yes it is present in the project.

[Marc - Devoteam]

HI @Jira Admin 

Ok.

But within the API you can address the Organization field only via it's ID and the option needs to be defined as with its ID as well.

Example:

"customfield_10500": [
{
"ID": 4
}
],

[Jira Admin]

Already we have tried with Id but it's not working same as before.