So have you sent the confirmation since and have they accepted? If not then I would go ahead and re-list.
If they did confirm but you haven’t heard from them then I would suggest you relist but only confirm someone else if you don’t hear back from the original NZ sitters. Does that make sense?
Did you have a video chat with the NZ sitters? For future reference don’t just rely on messaging through THS website/app but make sure you get their mobile number and email address so you can try to contact them by all those methods.
Oh and if you’d like us to check out your listing and give you feedback to improve it, you need to attach it to your profile. Here’s how to do that: