Go to their secured email and email the documents including a current prescription for the appropriate machine (bipap vs autosv vs cpap etc). They have a call back number in the secure email, give them a call if needed. I got mine replaced after a lot of frustration but it was worth it.
I don't have a current prescription because the loaner machine was given to me instead. I did have one when I ordered the original of course. Though I lived in a different country back then.
But I can probably get a new prescription. Where do you find this secure email? I don't know what you mean, I only have the email address they emailed me from. Maybe that secure email is a US thing?