Many thanks! Looking at these number I assume this is the data format used by Microsoft Excel? Unfortunately, n8n doesn’t have a built in option to convert these.
If you control the source sheet, you could explicitly store these values as texts rather than date values.
If that’s not an option and you need to convert these values in n8n, you could use a Set node and an expression like {{new Date(Math.round($json["Created at"] - 25569) * 86400 * 1000)}} (found here). This would convert the Excel value in a Date value understood by n8n:
Hope this helps! Let me know if you have any further queries on this 