You could also email their CXOs. Many will appreciate direct (considerate) customer feedback that they may not be hearing from their teams. Claire Hughes Johnson, Stripe's Chief Operating Officer, who presumably oversees service/support, is at claire@stripe.com¹.
¹ FYI, this email was publicly discoverable via search engines and took a few seconds to find.
xyzzy_plugh
A quick Google shows she stepped down as COO over a year ago, so possibly not a great example.
CharlesWOP
Thanks for posting that. So does Stripe just not have a COO at the moment?
¹ FYI, this email was publicly discoverable via search engines and took a few seconds to find.