i'm having so much trouble with my LG Rumor cell phone!?!?

[Emily]

so i had a white LG Rumor.
but it started having MAJOR problems and the screen went white. i couldnt use it at all.
so they gave me another rumor (black and blue) for $50 as a replacement.
and i have unlimited internet,texting, etc.
but when i went to go on the internet, it would tell me The network is preparing your services. Please wait.
it never said this on my old phone. i was a little concerned.
right after that message it would say Error 7. Network timeout. Please, try again.
i tried a couple times and had no luck.
so i called customer services.
they went through everything with me and we tried every trick in the book.
no luck.
i went to a Sprint (NYSE: S) repair store the next day and they couldnt fix it and told me to get a new one sent in the mail.
so i called and got a new one sent to my home.
the next day the package arrived and i open it up and instead of sending me the exact same phone, its green.
so i had to call them and tell them i ordered a black one. not green.
now i had to wait another day for the newest black lg rumor to show up at my house.
when it did (today) i was excited to finally be done with all of this.
i brought it to the store and got everything transfered and activated. and when i went to go on the internet, same message. Error 7 Network timeout. Please, try again.

Why is the Rumor having these problems now?
my old one didnt. is it just the black and blue ones for some reason?
please help. i just want my phone to work correctly!