Since manufacturers of these devices often don't provide official support sites, you must rely on community repositories and firmware archives:
If you own a budget-friendly TV box powered by the chipset (covering RK3228, RK3229, and RK3228A models), you have likely encountered performance lags, app compatibility issues, or the dreaded boot loop. The most common solution to breathe new life into these devices is reinstalling the operating system using the firmware version Android 7.1.2 NHG47K . android rk322x box rk322x box 7.1 2 nhg47k firmware download
Several developers host stock and modded ROMs on GitHub. Look for files named RK322X_7.1.2_NHG47K_MultiWiFi_*.img . Since manufacturers of these devices often don't provide