Hello and welcome to the Stacks
one quick note please break future posts into paragraphs you wil get more and better responses if the stackers can read it easier, thanks.
When you go to options>advanced options>media card
make sure your settings are the following:
Media card support: on
Encryption mode: none
Mass storage mode: on
Auto enable mass storage mode when connected: yes
And of course you need to have a Micro SD card in your pearl
If that doesnt work I would get the phone exchanged, other than t-mobile RIM the maker of the phone also has a 1 year warranty.