Problem statement
We’ve recently been having issues with Auth0. People who use SMS for authentication have been asked by Auth0 to provide a code, but no code has been sent. We saw error messages “no capacity for SMS 2FA”/“SMS per tenant rate exceed”, and too_many_sms_per_tenant in tenant logs.
Cause
When you get the “no capacity for SMS 2FA”/“SMS per tenant rate exceed” message, you’ve reached the limit of 100 messages per tenant.
Solution
The Auth0 provider is intended to be used only for testing. For production use, you will want to configure your own SMS delivery provider with either Twilio or a custom SMS gateway.