Currently, when I submit a new form, there is no problem (WebFormSubmission::create() and save()). When I reload this Webform submission and modify some fields of form and record it, there is no problem (WebformSubmission::load() and save()).
But I not able to create a new Webform submission from this previous Webform submission. Aim is to have 2 independant submissions.
I tried to create() and save() after moditication but something is wrong.