Validation error when trying to change applicationProtocol port of ScServiceStableConfig (ECS Fargate Service Connect)

Hello! I attached a Service Connect configuration to my ECS Fargate Service with the following config:

    portMappings = [{
      containerPort = 3001,
      hostPort      = 3001,
      name          = "api-3001",
      protocol      = "tcp",
      appProtocol = "http"
    }],

Then later I decided to change the applicationProtocol to null as I was getting a 426 status code back. When trying to do so (via terraform and web console) I got:

The following config cannot be changed for a SC service. Previous config: ScServiceStableConfig(applicationProtocol=http, transportProtocol=tcp, ecsServiceArn=<arn-of-my-service-hidden>), current config: ScServiceStableConfig(applicationProtocol=null, transportProtocol=tcp, ecsServiceArn=<arn-of-my-service-hidden>)

I tried to go to my AWS Cloud Map namespace and delete the entries related to my Service Connect to see if it would recreate the api-3001 port but it didn't work and would still fail when trying to attach the client alias for Service Connect in the webconsole.

The only workaround I found was creating a new port mapping name and creating a new client alias.

What could be causing this? Are portMappings and client aliases in Service Connect immutable?