Creating application in AWS elastic beanstalk using docker platform

Im trying to create an application in aws elastic beanstalk using docker platform and platform branch Im using is "ECS running on 64bit Amazon Linux 2" and im using Dockerrun.aws.json, but it gives me the below error msg

1. The EC2 instances failed to communicate with AWS Elastic Beanstalk, either because of configuration problems with the VPC or a failed EC2 instance. Check your VPC configuration and try launching the environment again.

2. Stack named 'awseb-e-zmaq9ay7mj-stack' aborted operation. Current state: 'CREATE_FAILED' Reason: The following resource(s) failed to create: [AWSEBInstanceLaunchWaitCondition].

3. Environment health has transitioned from Pending to Info. Initialization in progress (running for 15 minutes). None of the instances are sending data.

I tried using all the combination of instances nothing works.I used postgress db and the instances are db.t3.small and the arm architecture instance are db.t4g.small.