How to dial from US to Italy

tmobile is crap! I came back to Tmobile from Verizon to save money but have been giving the most run around. I can't seem to get a competent rep to verify my virtual gift card and the numbers on it as well to associate it with a live zip code, preferably my own which makes sense, right? They have me on hold for hours for the basic of the basic tasks which takes away from my productivity in doing my own job.