Samsung galaxy s4 not working with international SIM card (Verizon)

[jm432]

I landed in Israel today, where i had an Israeli SIM card waiting. I called Verizon 3 times in the last two weeks to make sure the phone would work with the foreign SIM. They all said it would, although one woman told me to change my phone to GSM. I put in the new SIM card and immediately received a text message that a friend sent me to my Israeli number. But my reply never went through, and now my phone doesn't have data and won't make or receive calls or texts. I've tried global, GSM and CDMA, but nothing works. Desperate for any suggestions!