To expand on post #2, do use whatever alternate methods are available to contact the vendor. Said differently, don't count on the reliability of email as you might've done in the past.
I've personally had better luck using Facebook Messenger to solicit a response from a vendor, versus using a legacy email address, provided they've a presence on FB. The same may be true for Instagram, etc.
Determining what e-conduit a vendor is willing to use can be annoying for the customer, but that's just the way it sometimes goes these days.