SD card, or SIM card? You said SD in the thread title.
If Metro put in their SIM card, why didn't they check it and make sure you're activated on their network. Do they not do that in-store?
I have the same phone, so this much I know. The SIM card and the SD card both use the same tray and slot on the phone. The SIM snaps into one side, while the SD card snaps into the other side. While both cards are almost the exact same size, there is enough difference that it's hard to mix them up. And, the tray only goes in one way.
Now, I guess it's possible to force the SIM into the wrong side, and it's facing the wrong way in the tray. But it think that would also mess the tray up enough so that it would slide in properly. Unless they forced that in too.
Check with that video to make sure it was at least installed right.
If it still doesn't work, go back to Metro and tell them you aren't leaving until they check its activation.
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