It seems like you are trying to create more than two VMs with a public IP address using the 30-day trial version of Microsoft. The trial version of azure subscription has some restrictions, and creating more than two VMs with a public IP address is not allowed.
If you want to create more than two VMs with a public IP address, you will need to upgrade to a paid version of Microsoft. However, I would like to clarify that creating VMs with a public IP address is not the only way to access them. You can use Azure Bastion on a free trial subscription. Azure Bastion is available on all Azure subscriptions, including free trial subscriptions.
To use Azure Bastion, you need to create a virtual network and a subnet for your VMs. You also need to enable the Azure Bastion service for your virtual network. Once you have done this, you can connect to your VMs through the Azure portal using the Azure Bastion service.
Ref: https://learn.microsoft.com/en-us/azure/bastion/bastion-overview
Also, if you are using the free subscriptions for training/learning, you can create one more new test subscription and use it.
If you have any other questions or concerns, please let me know.
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