This is typically caused by sensor overload from an extremely bright subject against a very dark background. When pixels receiving the bright phone screen become saturated, excess charge can leak into neighboring pixels, creating a streak or band. With CMOS sensors, this can also show up as a readout artifact similar to CCD “smear,” though CCDs are usually more prone to it and often show vertical streaking instead. In your case, the horizontal reddish band is consistent with a CMOS readout/saturation effect. It’s most noticeable in very high-contrast scenes and may become more obvious if you heavily brighten shadows or recover exposure in post.