Do subnet names have to be unique ? I am getting error below.

Diagnostics:
  azure:network:Subnet (GatewaySubnet):
    error: Duplicate resource URN 'urn:pulumi:test::vnet-a360-new::azure:network/subnet:Subnet::GatewaySubnet'; try giving it a unique name

yes and no. This is not an Azure error, but a pulumi error. It says that the pulumi resource URN already exists in this stack.

Yeah, thank you @colossal-room-15708 I just changed logical name to be unique, and leave real name , so it is looking good now 😉