SharePoint List button not working!

For setValue in column formatting, a single‑select Person field actually expects the person token directly, not an object.

For a single‑person field, this is the correct pattern:

"CheckedOutByColleague": "=if([$Status] == 'IN', , '')"

After several iterations and guidance from Copilot, I was finally able to produce the correct working JSON.

{
  "$schema": "https://developer.microsoft.com/json-schemas/sp/v2/column-formatting.schema.json",
  "elmType": "button",
  "style": {
    "padding": "6px 12px",
    "border-radius": "6px",
    "border": "1px solid",
    "cursor": "pointer",
    "font-weight": 600,
    "background-color": "=if([$Status] == 'IN', '#107c10', '#d83b01')",
    "border-color": "=if([$Status] == 'IN', '#0b6a0b', '#be3700')",
    "color": "white"
  },
  "attributes": {
    "title": "=if([$Status] == 'IN', 'Check this key OUT', 'Check this key IN')",
    "aria-label": "=if([$Status] == 'IN', 'Check this key OUT', 'Check this key IN')"
  },
  "txtContent": "=if([$Status] == 'IN', 'Check Out', 'Check In')",
  "customRowAction": {
    "action": "setValue",
    "actionInput": {
      "Status": "=if([$Status] == 'IN', 'OUT', 'IN')",
      "CheckedOutByColleague": "=if([$Status] == 'IN', , '')",
      "WhenCheckedOut": "=if([$Status] == 'IN', @now, '')"
    }
  }
}

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