[helsontaveras18]

And then you switch to another SMS provider, which may be costly from an engineering perspective, but clearly worth it if you’re getting slammed with botnets and Twilio doesn’t care.

Absolutely, dispute the charge.

[acover]

Which providers don't have this problem? Does AWS prevent you sending SMS to premium numbers?

[PenguinCoder]

Almost any provider will have these sorts of problems. In my experience though, SignalWire has been great for customer service and working with.