Ticket migration and date of resolution / closure

Hello,

We are trying to develop a process to migrate one of our client’s tickets into Freshservice (from Zendesk).

Everything works perfectly except for the closure date, which is always set to today’s date.

We are trying to find a workaround for this issue, but we cannot find any field accessible via the API that would allow us to modify this value.

We also tried setting due_by and fr_due_by, but regardless of the value provided, the API rejects it: either because the value is supposedly earlier than the ticket creation date (which is incorrect, since we are of course migrating the original creation date), or because the SLA does not apply to a closed ticket (which I understand, but the same issue occurs when migrating a ticket in an open status).

Any ideas?

Helpdesk Migration, the online tool, migrates this field perfectly. I would like to know whether a specific API must be used or if there is an undocumented workaround.

Thank you!