I need to reorganize several licenses, how can I contact MatLab customer support since the number listed on the website isn't valid?

I need to reorganize several licenses and the [phone] press 1 number is giving me the repetitive beeping tone that usually indicates a dead number.

Does anyone know how to talk to customer service?

~Jennifer

EDIT: I suppose it could be a busy signal, but I've tried three times from two different phones and had someone else type to make sure I was calling the right number.