/form/:id/submission not returning all submissions of a form

Hi,

I'm trying to get all submissions for a Form by using GET /api/v2/form/{id}/submission.json but each time when I'm requesting a page of 50, I'm receiving a random number of submission (like 41), so at the end, instead of having 100k submissions (page per page), I have only 7576 submissions...

Do I miss something?
I don't have this issue with partial submission, I have correctly the same number of submissions in the interface and in the API.

Thank you for your help