Which guide are you using?
PWM and SPI are different
I use SPI, which is pin 19 and 23. ground pin is 9
Make sure you have everything connected before loading/sending the json file. It will not work with a partial setup
I have a ws2812b ledstrip with one data, must conect to bcm 18, 12 or 13.
Pwm 28xx-spi or 28xx fot rpi 1.2.3.
My spi is on.
Using guide 3 wire-pwm and other guides.
Read that other having problems with newer OS like Le and OSMC
I bought a Arduino uno today and i'm going to connect it to my pi. It's a easy way
My ledstrip is working! With Arduino strandtest.