Old Task Definitions Becoming InActive on Creating New Definitions with serverless - amazon-web-services

Question

I am Using Serverless to create task definitions and use this to work with step functions.
Here When I update my task definition in serverless and deploy it, prev task definitions become inactive and not able to use them further.
How to not make inactive prev Task-definitions?
Below is my serverless.yml
service: my-service
useDotenv: true
provider:
name: aws
runtime: python3.8
stage: ${opt:stage, 'alpha'}
region: ${opt:region, 'ap-south-1'}
profile: ${opt:profile, 'default'}
memorySize: 1280
timeout: 600
plugins:
- serverless-step-functions
package:
individually: true
patterns:
- '!./**'
stepFunctions:
stateMachines:
...
...
validate: true # enable pre-deployment definition validation (disabled by default)
resources:
Resources:
fargateProjectCluster:
Type: AWS::ECS::Cluster
Properties:
ClusterName: ${self:service}-${self:provider.stage}
fargateTaskDefinition:
Type: AWS::ECS::TaskDefinition
Properties:
ContainerDefinitions:
- Name: new_definition
Image: ...
Privileged: false
ReadonlyRootFilesystem: false
Essential: true
LogConfiguration:
...
...
Cpu: ${env:CPU_UNITS}
ExecutionRoleArn: !GetAtt ecsTaskExecutionRole.Arn
Family: "${self:service}-${self:provider.stage}"
Memory: ${env:MEMORY_UNITS}
NetworkMode: "awsvpc"
RuntimePlatform:
OperatingSystemFamily: LINUX
CpuArchitecture: X86_64
RequiresCompatibilities:
- FARGATE
TaskRoleArn: !GetAtt fargateTaskRole.Arn
fargateCloudWatchLogsGroup: ...