This error is raised when an update request is sent to a cluster that has been placed into read-only mode. Clusters can be placed into read-only mode for one of several reasons, but the most common reason is due to an overage.
If you're seeing this error, check on your cluster status and address any overages you see. You can find more information about this in our Metering on Bonsai documentation, specifically the section "Checking on Cluster Status". If you're not seeing any overages and the cluster is still set to read-only, please contact us and let us know.