The Raspberry Pi 4 of the robotic club has always been powered by phone charger adapters without encountering any serious issues so far, only occasionally receiving low voltage warnings. Today, when I couldn't find the usual adapter (33 watts), I plugged in another one from the same brand (Xiaomi) with 67 watts, and after 2-3 minutes, I received the low voltage warning again. Both adapters have fast charge feature, the voltages are the same, but the one with 67 watts has a higher ampere rating. Shortly after, about 5 minutes later, while editing a .py file, RealVNC Viewer froze. I noticed that it disconnected from my hotspot. Even after unplugging and replugging the Raspberry Pi, there was no response, the red LED was blinking, and the green LED was definitely not lit.
What could be the issue? Online sources suggest low voltage for the blinking red LED, but it doesn't make sense since the adapter I always used shouldn't suddenly produce low voltage. My guess is that for some reason (which I'm really curious about), the adapter I used today tried to use the fast charge protocol and might have damaged the Raspberry Pi.
Extra information: When I connect it to my laptop's USB port, the red LED blinks rapidly, approximately every 1 second with the 33-watt adapter, and approximately every 2 seconds with the 67-watt adapter. What does this imply?
What could be the problem, and what can I do for repairs?
