Lookup field mapping can't update User selection field when source field is Created by or Updated by.

When lookup mapped field is User selection type, and source field is Created by or Updated by.

The document said the case is supported:

Fields That Can Be Specified for “Field Mappings” (cybozu.help)

User selection field can be updated in editor page of Kintone, it can’t be updated successfully by API.

Hello Linner,

Please share the code you are using to make the API call and the error message you are getting.

Thank you

Hello, Genji,

This is the setting of the lookup field:

Invoke the following code, it doesn’t take effect:

var body = {
    "app": 59636,
    "id":"353" ,
    "record": {
        "Lookup_0": {
            "value": "253"
kintone.api(kintone.api.url('/k/v1/record', true), 'PUT', body, function(resp) {
        // success
    }, function(error) {
        // error

Hello Linner,

Your script worked fine for me regardless the source field was “created by” or “updated by.” 
The problem might be due to the settings in your fields or it could be related to permission.

Could you check into that?