Submit a Ticket
The more specific you are, the faster the first reply. A URL and a screenshot usually cut the fix time in half.
A URL beats a description. “Checkout step 2 on mobile Safari” gets fixed hours sooner than “the site is broken”.
New plugin, new theme, someone edited a page — knowing that usually points straight at the cause.
Send it in the WhatsApp thread or reply to the confirmation email. Half of all bugs are obvious the moment we see them.