Thank you for your answer ChrisJ4203.
It's not just a hold. I followed your advice and contacted iTunes support and also Netflix's support.
First i contacted iTunes support and they've recommended me to ask Netflix if i am eligible for a free trial and if i want a refund my subscription will be canceled immediately . Netflix told me that I am 100% eligible and is not normal that I have been charged. Afterwords i replied back the person who is managing my case at iTunes support and told him what Netflix said and if the only way to get my money back is to loose the whole subscription at Netflix and not benefit from the free trial, then i agree because it supposed to be free.
In my opinion the purpose of a free trial is to test the services and at the end of it to decide to go on or not with the services if you like them or not.
So, since Netflix confirmed that i am eligible for a free trial i consider that is not corect to be charged for it.
Now i am waiting for a response from iTunes support.
I wish you a good day!