Container App fails to resolve registry name

Hello, I have an issue with Azure Container Apps. When I mount one using a brand new VNet on a subnet with default inboud/outbound rules, if works like a charm. But When I mount one on our standard VNet (same NSG on the subnet), it can't pull the image from our container as it fails to solve the registry name. I mounteded the hello world image on both configuration, and NsLookup and the console shows that there are differences in the name resolution: On the VNet where it does not work, it solves the container registry like this:

On the "Brand new" VNet, where it works, the resolution seems recursive:

Both VNets are using standard Azure DNS. Both subnet use the same NSG Could someone help solving this issue ? Thank you