DTL ArmTemplate - deploy vm and link to loadbalancer

Question

I have a DevTest Lab with vNet and subnets configured and set to allow shared IPs. When I create new VMs associated with the same subnet, most of the time they properly associate to the same LoadBalancer and BackendPool. However, sometimes new VM deployed under the same conditions creates new Public IP, LoadBalancer and Availability Set.

Trying to understand and control that behavior. Wondering if there is a specific condition that triggers that and if there is an approach to manage that via ArmTemplates. So far I was not able to find any answers and hope you can shed some light. Thank you!