Converting date to Unix UTC millisecond

Converting date to Unix UTC millisecond

Hello, 

I need to create a function that will convert/return my date from Calendly in the following format: "2022-08-10T14:00:00.000000Z" to a UTC timestamp value in milliseconds. Can someone help? 

I tried the following: 
  2. string UnixDate(string myTime, string unixTime)
  3. {
  4. unixTime = myTime.unixEpoch("UTC");
  5. return unixTime;
  6. }
However, the API client I am sending it to is viewing it in the wrong time zone. Not sure what I am doing wrong. I would really appreciate any support.