Running in App script, google sheet.
I get timestamp from API and return this result:

[[1.6370611672429312E18], [1.63706107263277082E18], [1.63706100204943616E18], [1.63706094340754534E18], [1.63706078474499994E18], [1.63706064715950106E18], [1.63706061367677235E18], [1.63706061367677082E18], [1.63706061367676902E18], [1.63706061367676749E18], [1.63706061367676595E18], [1.63706061367676442E18]], 

Now I want to convert this timestamp to date to be like that: 10/28/2021 10:30

I try this code: var convertDate = Utilities.formatDate(timestamp, "GMT", "MM-dd-yyyy HH:mm:ss"); but not working any suggestoin

>Solution :

Assuming those timestamps are in nanoseconds, create a Date by dividing the timestamp value by a million.

const timestamps = [[1.6370611672429312E18], [1.63706107263277082E18]];
for (let i = 0; i < timestamps.length; i++) {
  const timestamp = new Date(timestamps[i][0] / 1000000);
  const convertDate = Utilities.formatDate(timestamp, "GMT", "MM-dd-yyyy HH:mm:ss");
}