unstable PWM operation

[ShultsAlexey]

Hi I connected the laser according to the instructions: https://marlinfw.org/docs/configuration/2.0.9/laser_spindle.html#laser/spindle-configuration-(2.0.9.x) Using M106/M107 commands ...BUT THE LASER FLASHES. here is an example of work: https://www.youtube.com/shorts/_b1xg4CLyhA

I tried to connect to the PWM generator, everything is fine.

What could be the problem?