tmobile sim not working on cingular bb 8800

[radp]

so i'm new here, and i've been searching a hell of a lot before i posted this.
so i hope i don't make anyone angry.
but anyway, i bought this cingular 8800 online and i am currently with t-mobile. when i put my t-mobile sim card in, i don't get reception or service at all. i was starting to think my device hasn't been unlocked, but i did 2 things.
first, i checked the options>advanced options>sim card> and everything says disabled. that means it's unlocked right? correct me if i'm wrong.
second thing i did is call cingular and t-mobile to find out what's wrong, and they both said i should have gotten a prompt when i put my sim card in, which says enter the unlock code or something.

please help me with this, i really want to start using this blackberry!!!!!
is it possible i need a new sim card?

thanks guys.
don't get mad if this has been posted before.

[JSanders]

radp... welcome to the BBForums. We (normally) aren't a bunch of jerks who get mad at first time posters... so no problem.

If you SIM window as you described stated all was "disabled", the the device is unlocked from the branded carrier. That should not be a problem. You won't get a prompt or message to enter an unlock code again after inserting the SIM.

But, do you get any message at the top of the 8800 screen, such as SOS?

[radp]

oh no man. i get nothing. everything looks like it works fine, the reception display just shows an "x"

what else should i do?

[radp]

this is the only thing i could think of... is it possible i need a new sim card? do you think that would work or would that be a waste of money.

[JSanders]

Yea I think it is worth it.

[radp]

has anyone else experienced this problem, where they have an unlocked phone and have a different service. then when they put the sim in, they can't make phone calls?

i really want to use this blackberry.

[Sith_Apprentice]

options > mobile network > make sure the network selection mode is not set to manual. make sure it is automatic. also you can change it to manual and scan for networks to see if you can connect, then move back to automatic.

[JSanders]

ahhhhhhh, good suggestion, Sith, thanks.

[radp]

alright. so now what i did is i went to t-mobile to try buying a sim card. as i got to the store, suddenly i have reception. 2 bars at the most. i was like cool.
so i just left right away, and as i went to get some food about 1 mile away, no more bars. but it did "sos" for a bit on the way.
after i got food i went back, and i had the 2 bars again. wow.
i decided to try buyin a new fresh sim card. i put it in and i still had 2 bars.
what do you think is wrong with this now?

is there anyway of tweaking my antenna?

[radp]

oh ye, and at my house i never have reception and there is no available networks around my house.