If your new Beyonwiz T2 cannot record shows from 3 different TV networks at the same time you should check that you have correctly connected the included antenna loop cable from 'Tuner A Out' to 'Tuner B In' and also correctly connect the USB 3rd tuner's antenna cable to 'Tuner B Out'. See the following diagram.
If you have your new Beyonwiz T2's antenna cables connected as shown but still cannot record shows from 3 different TV networks at the same time please contact Beyonwiz Support. If Beyonwiz Support cannot assist you in getting it working or suspect the USB tuner is faulty they will send you a replacement USB tuner (at no cost if the Beyonwiz is still under warranty).