Ive got an Alcatel with a Telstra Sim. Had no problem. They use a different size sim. If you have problems, go into a Telstra Shop, they will fit and check it for free.
Here is how:
From the main screen, press the MENU key.
Tap "Settings."
Tap the "Bluetooth" slider to turn it on/off. When Bluetooth® is on, the slider will turn yellow.
To return to the main screen, press the HOME key.
That should be it.
Hope it helps :)
You can do it by hard reseting your phone & wiping all your data. To do this follow the below steps :
Start by switching off the cell phone by holding the Power key
In the next step press and hold Volume Up + Power button for a couple of seconds.
Release held keys when the Recover Mode appears on the screen.
Use Volume buttons to sroll to option "wipe data/factory reset", and confirm that with Power button.
Choose "Yes" from the menu, and confirm it with Power key.
Now accept option "reboot system now" using Power key.
Success! The hard reset has just been performed. https://support.bell.ca/mobility/smartphones_and_mobile_internet/alcatel-onetouch-idol-x.how_to_perform_a_hard_reset_when_my_alcatel