Hello @Daniele Olivieri ,
Did you check, just for testing purposes, if the deployment works in a different region?
In case of a deployment issue you can check the article below on how to obtain more information to identify the cause:
https://learn.microsoft.com/en-us/azure/azure-resource-manager/troubleshooting/find-error-code?tabs=azure-portal#deployment-errors
If you are stuck i would suggest to raise a ticket with the Azure Networking team to investigate this problem.
I hope this helps!
----------
Please don’t forget to "Accept the answer" and “up-vote” wherever the information provided helps you, this can be beneficial to other community members.