How about AICKSN water purifier?

Germicidal ultraviolet lamps use short wavelength (UV-C) to kill microorganisms found in the water. Ultraviolet lamps produce UVC light to sterilise the water by treating bacteria. Ultraviolet lamps should be replaced regularly as the germicidal rays will gradually deplete. If the ultraviolet lamps are not replaced at regular intervals there is an increased likelihood of bacteria and viruses entering the water supply. It is also recommended that the quartz sleeve that houses the ultraviolet lamp is cleaned periodically (depending upon the quality of the water) or replaced if damaged or if staining can’t be removed.

Reverse osmosis feed water quality requirements and specific solutions

Except for some special resins that cannot be regenerated, ultrapure water polishing resins are generally able to be regenerated, but the regeneration of ultrapure water polishing resins is a little more difficult than that of other resins, and the detailed steps of ultrapure water polishing resins can be divided into layering, regeneration, cleaning, mixing, and positive washing.

When the home water purifier malfunction, do not panic, carefully observe the failure phenomenon, check and deal with the above strategies and guidelines, I believe that most of the problems can be solved, so that the water purifier continues to provide quality drinking water for the family.