# 30031: Invalid MaxRate

Log Type: APPLICATION

Log Level: ERROR

## Description

`MaxRate` must be a valid `float`. Twilio returns this error when the value you provide is not a valid floating-point number.

### Possible causes

* You provided a nonnumeric value for `MaxRate`.
* You set `MaxRate` to `0` or a negative number.

### Possible solutions

* Set `MaxRate` to a positive `float` value.
* If you are configuring Messaging throughput, choose a rate that matches the sending capacity you need. Twilio measures throughput in messages per second and queues requests that exceed available capacity.

#### Additional resources

* [Account Based Throughput Overview](/docs/messaging/guides/account-based-throughput-overview)
* [Build to scale: queueing and latency on Twilio](/docs/messaging/guides/scaling-queueing-latency)