Where/How did you try to contact them?

Did you send an email to

If so, try to wait a bit longer, as it looks like they've been offline for the last couple of days. https://bitcointalk.org/index.php?action=profile;u=1003345

I do agree with you though, this is not something that should happen, and chipmixer should give clarity faster about your issue, and whether it's a fault on their end, or yours.