Xiao and stripled. Only first 20 leds work

hi,
I am.new on seeduino xiao and
struglling for few days to figure out why only first 20 leds are working from.my bandled.

I have 1m of bandled (140 leds)/12v from aliexpress,ws2815. (Scl,sda,+,- to i2c xiao)

I have done several similar.projects under arduino nano/uno, and all of them works.

If I decrease the leds number bellow 20 ,again…all ok.Seems like max numbers.of led = 20 in xiao.
Any hint get a like:)

Seems that the bandled is broken.