Tyler Ward shared detailed article about not working USB-C chargers with Raspberry Pi 4B.
The problem is in design of USB-C of Raspberry Pi. HW designers used only one pull-down resistor for both CCx pins.
This solution is not complain with USB-C standard and in case you are using e-marked cable (what is fully complained with USB-C standard), your USB-C charger sets your device, your Raspberry Pi, like "Audio Adaptor Accessory" based on setting of resistors.
Due to this wrong design, USB-C chargers (with e-marked label) doesn't work with your Raspberry Pi. The power is refused. If you buy non e-marked label, there is possibility it will work without problem, because the low-cost cable contains only connection to one CC pin.
Of course, the USB-C power supply made by Raspberry Pi is fully working (and without e-marked label).
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