The VPC service allows you to create private, isolated virtual networks. In a VPC, you can manage private IP address ranges, subnets, route tables, and network gateways. ECSs, BMSs, databases, and some other applications use secure networks created in VPCs.
Subnets in a VPC cannot be deleted if the subnets are used by the following resources:
Check whether the subnet is used by the preceding resources. If yes, delete all resources in the subnet and delete the subnet.