That's what I'm saying. They have to MANUALLY activate your phone for your account. If they don't know it exists, there you can't use it. I had another phone from a different start-up years ago, and the same was true for that phone. If they don't "ok" it, you can't use it. The bands that the Pro 1 uses doesn't mean much if they block you from using their services. Also, what do you mean by which SIM card? Are you talking size? Sent from my Nokia 9 using Tapatalk