If your phone is asking for a "Network PIN" or "SIM Network Unlock PIN," follow these steps:
Since the official Huawei portal is closed, you must use one of these alternatives: SIM Network Unlock PIN: Meaning & Fixes - iMobie huawei 16 digit unlock code calculator
Many carriers provide this for free if your contract is finished or after a certain period of active service. If your phone is asking for a "Network