I found a code seller on eBay did the *#06# and got my IMEI, received the code and it did not work. Tried this multiple times, with multiple vendors and they all sent the same code.
But, I found out what was wrong. With all the popping the SIM tray in and out I realized that their was an IMEI written on the SIM tray, but it did not match with the IMEI on the phone.So, with nothing else to lose, I entered the IMEI number on the SIM tray, received the unlock code, and to my surprise, my phone was SIM unlocked!
If anyone is having trouble unlocking, try checking to see if the IMEI on the SIM tray is different from the IMEI on the phone, it worked for me!