I recently downgraded to the free plan and the build/deploy failed. The build log says:

"Free plan deployments must be serverless. Please go to your service settings and turn on the serverless flag."

However, I already have the serverless flag on:

"Serverless

Containers will scale down to zero and then scale up based on traffic. Requests while the container is sleeping will be queued and served when the container wakes up. Docs↗

Enable Serverless"

What should I do? Thanks!