检查以下是否已正确设置ENI的网络和子网。如果已完全正确设置，可能是缺少NAT网关。在这种情况下，需要为VPC创建并配置NAT网关。以下为配置NAT网关的Python代码示例：

import boto3

# 定义VPC和子网的ID
vpc_id = 'vpc-xxxxxx'
subnet_id = 'subnet-xxxxxx'

# 创建EC2客户端
ec2 = boto3.client('ec2')

# 创建并分配Elastic IP
response = ec2.allocate_address(Domain='vpc')
eip = response['PublicIp']

# 创建NAT网关
response = ec2.create_nat_gateway(AllocationId=eip, SubnetId=subnet_id)

# 等待NAT网关创建成功
nat_gateway_id = response['NatGateway']['NatGatewayId']
waiter = ec2.get_waiter('nat_gateway_available')
waiter.wait(NatGatewayIds=[nat_gateway_id])

# 更新路由表
route_table_id = ec2.describe_route_tables(Filters=[{'Name': 'vpc-id', 'Values': [vpc_id]}])['RouteTables'][0]['RouteTableId']
ec2.create_route(DestinationCidrBlock='0.0.0.0/0', NatGatewayId=nat_gateway_id, RouteTableId=route_table_id)