Huawei P30 Lite Mar Lx3a Emui 12 //top\\ - Firmware

You need the "Full OTA" image. Since the MAR-LX3A is a Latin American model, you generally want the firmware tagged for that region (often labeled C185, C432, or specific carrier codes).

There are two methods to update your Huawei P30 Lite to EMUI 12: