You might need to add a lambda permission to allow eventbridge to invoke lambda:
{
"Effect": "Allow",
"Action": "lambda:InvokeFunction",
"Resource": "arn
awslambda:_`region`_:_`account-id`_
function_`function-name`_",
"Principal": {
"Service": "
events.amazonaws.com"
},
"Condition": {
"ArnLike": {
"AWS:SourceArn": "arn
awsevents:_`region`_:_`account-id`_:rule/_`rule-name`_"
}
},
"Sid": "InvokeLambdaFunction"
}