Blackberry Curve won't send SMS text to certain people

[bbcurve93]

I got my new blackberry curve yesterday and when I tried texting, it wouldn't send texts to anyone at all (my phone said it sent the texts but the recipients never actually got the text). I called customer service and they had me take out the battery and restart the phone which allowed me to successfully send texts to two of my family members, so I thought it had been fixed- wrong. I tried texting my friends and it didn't work. Today it started working for a few of my friends but not for others. Another family member said that my phone hadn't been properly registered so he registered it and it worked for the remainder of the friends that I had tried to text. Then I realized it was texting pretty much everyone except my father (who has verizon). I really don't understand why my phone is choosing certain people to successfully send texts to and it's very frustrating..does anyone have any idea what's wrong or how this issue can be fixed? Thank you.