Each one of these systems you are speaking of (orders, newsletters, and even support) operate on separate servers and systems. E-mail is not a "toy" to service providers like Yahoo, and because of spam laws some can be overzealous. The support system uses an extra verification step. It is very likely that Yahoo is blocking you from even receiving the reply back from the system, so yes, this would be a service provider side issue.
You seem to be having trouble reading or understanding. I'm going to go with the latter. Considering we get thousands of support tickets in a week from people using the form, I'm going to, again, maintain what I've already said with regards to your situation.
I am certainly not interested in a back and forth with you. You've now been told TWICE in this very thread, minutes apart, what to do to receive support. The next move is yours. If you want to argue or debate...go elsewhere.