red led in smd module

[ali_aam]

in each of smd module 3 led and resistor are series.
after 2 or 3 days one of leds turn off but tow other leds remains bright.
can any one explain this video's and picture.

 

[(*steve*)]

Maybe you've destroyed some of the LEDs.

These don't already to be addressable LEDs, so I'll ignore that as a possibility.

When you have killed, or nearly killed, a LED then you often find they either don't come on immediately, it require a higher current to turn on, or are unusually dim.

Since semiconductors tends to fail short circuit, failures tend to cascade.