Initializer step function is failing due to IAM error

After deploying the aws power tuning in my account and trying to execute it,The Initializer step fail with the following error

` "cause": {
"errorType": "AccessDeniedException",
"errorMessage": "User: arn:aws:sts::xxxxxxx:assumed-role/serverlessrepo-aws-lambda-power-tun-initializerRole-l576tllQUOWO/serverlessrepo-aws-lambda-power-tuning-initializer-6adFhGV4OkoV is not authorized to perform: lambda:GetFunctionConfiguration on resource: arn:aws:lambda:xxxx xxxxx:function:xxxx:$LATEST because no identity-based policy allows the lambda:GetFunctionConfiguration action",
"trace": [
"AccessDeniedException: User: arn:aws:sts::xxxx:assumed-role/serverlessrepo-aws-lambda-power-tun-initializerRole-l576tllQUOWO/serverlessrepo-aws-lambda-power-tuning-initializer-6adFhGV4OkoV is not authorized to perform: lambda:GetFunctionConfiguration on resource: arn:aws:lambda:xxxxx:xxxxxxx:function:xxxxxxxxx:$LATEST because no identity-based policy allows the lambda:GetFunctionConfiguration action",`

am deploying the app using AWS Serverless Application Repository (SAR)
While deploying I passed the following parameters

{
lambdaResource:"arn:aws:lambda:xxxxx:xxxxxxx:function:xxxxxxxxx",
securityGroupIds:"sg-xxxxxxxxxxx",
subnetIds:"subnet-xxxxxxxxxxxxxxx"
...... rest are default values
}
```
Execution time Params
```
{
"lambdaARN": "arn:aws:lambda:xxxxxx:xxxxxxxx:function:xxxxxxx",
"powerValues": [
128,
256,
512,
1024,
2048,
3008
],
"num": 10,
"payload": "{}",
"parallelInvocation": true,
"strategy": "balanced"
}
```
I have verified that the required Policies are attached to the Initializer lambda step function

`{
"Version": "2012-10-17",
"Statement": [
{
"Action": [
"lambda:GetAlias",
"lambda:GetFunctionConfiguration",
"lambda:PublishVersion",
"lambda:UpdateFunctionConfiguration",
"lambda:CreateAlias",
"lambda:UpdateAlias"
],
"Resource": "arn:aws:lambda:xxxxx:xxxxxxx:function:xxxxxxxx",
"Effect": "Allow"
}
]
}`

Note :

setting the Resource to :"*" , is working fine , but what if I need to specify the least permission and only apply the poly on the lambda ARN only