AWS Batch + EC2 batch does not create the EC2 instances to run the tasks

I try to run AWS Batch Jobs with EC2 instances for model training automation, the problem is that when I try to run them the job is created correctly but in EC2 no instance is created so the job always remains in RUNNABLE.

I deduce that the problem is related to the permissions and that I do not have enough permissions but I can not detect which ones and I can not find it in the AWS documentation.

I know it is not because I use an instance type g4dn.xlarge because amazon avilito me in the quota service. as for the instanceRole I follow the indications that mark this official guide of aws so I do not think it is the problem.

I cannot detect exactly the error.

I attach the json of my Compute environments in case it can be of help

{"computeResources": {"type": "EC2","instanceTypes": ["optimal","g4dn.xlarge"    ],"minvCpus": 0,"desiredvCpus": 0,"maxvCpus": 800,"allocationStrategy": "BEST_FIT","instanceRole": "arn:aws:iam::1234abcd1234:instance-profile/ecsInstanceRole","ec2KeyPair": "ec2-key-of-clouster-ecs-mvp","ec2Configuration": [],"launchTemplate": {"launchTemplateName": "training-ec2-launch-template","version": "5"    },"subnets": ["subnet-1234abcd1234","subnet-1234abcd1234","subnet-1234abcd1234"    ],"securityGroupIds": ["sg-1234abcd1234"    ]  },"serviceRole": null,"type": "MANAGED","state": "ENABLED","computeEnvironmentName": "training-ec2-ce3"}