Entra Inbound Provisioning API not setting accountexpiry for on-premise AD

Question

I am using Entra Inbound Provisioning API to add new user on-premise. I can successfully add a user, but I'm unable to set the accountexpire attribute.

Below is the link that I have followed to configure Provisioning API:

CLICK HERE

When I checked the documentation attribute in Local AD it shows that its of type long integer. However in Provisioning API mapping we are not able to specify "long integer". I was only able to specify it as string or integer and I tried both. Below is the C# code I tried to convert the date to a long integer but it did not work:

string endDate = "2023-12-31"
var expiryDate = DateTime.Parse(endDate).ToFileTime();

Please suggest a way to do this.