Interesting thing about the prepaid phone card

Finally got my mom's phone activated. If everything looks OK, I will inject $50 in the prepaid card so that mom can call me whenever she needed.

I used a T-Mobile Prepaid phone card. While the cost seems reasonable for a new phone number (just $6) with 10 minutes, it REQUIRED a TMobile phone. I realized it when I tried to use the serial number of my Moto E398, which I brought and used when I was in Hong Kong, and the registration failed. However, after I entered my TMobile Nokia 5300 serial number, the activation was completed. Of course, I did do some research online before I did that as I definitely don't want the new SIM card hijack my Nokia phone. It turns out that the serial number is just used for verification and support. It does not affect the regular calling.

So now the new SIM card is in the Moto E398 (a non TMobile phone) and my original one is in my Nokia 5300 (TMobile phone but already unlocked before my last Hong Kong trip). So far so good.