In order to unlock the SIM on your ZTE V72A tablet, you will need to submit your IMEI to CanadaGSM. Use the second link from Google search engine to access the unlock page for ZTE V72A tablet. CanadaGSM will send you back, via email, the unlocking code that you can use to unlock the device. Once you obtain the code, turn on the device, insert the number in the provided field and press OK.
Note: You can obtain the IMEI of your device by pressing the *#06#
keys.