DIAGNOSIS This is a symptom of insufficient power delivery to the monitor. The panel is drawing more current than the connected cable or source can provide, causing voltage drops.
FIX You must provide adequate dedicated power. Always use the two-cable setup for demanding use. Connect one USB-C cable from your source for video signal. Connect the second USB-C port on the monitor to a dedicated USB-C power adapter (at least 18W/3A) using the included cable. Do not rely on a laptop's USB-A port or a low-power battery pack for the second port.
IF THAT DIDN'T WORK The issue could be the specific cable. The flickering is often caused by the video cable. Replace the USB-C to USB-C cable with a certified, high-bandwidth one that explicitly supports 4K video or DisplayPort 1.4. Cheap cables lack the necessary shielding and conductors.
HEADS UP Enabling HDR mode increases power consumption and can trigger flickering if power is borderline. If you experience flickering, go into the OSD menu and disable HDR in the picture settings as a diagnostic step.