Blue Pill: Enable ssd1306 display via i2c

Hi everyone! I'm trying to learn how to program microcontrollers with C and stuck with trivial task.

I have blue pill, stlink v2 and ssd1306 oled display

I'm trying to enable all pixes on the display via i2c: https://gist.github.com/ksevelyar/5e6c0335aa5295a47fc80e82db088fa0

I've adopted this example: https://github.com/libopencm3/libopencm3-examples/blob/master/examples/stm32/f1/other/i2c_stts75_sensor/stts75.c#L23-L52

But it's not working, the display remains disabled.

The address of oled is 0x3C the command is 0xAF

Maybe I'm sending command in wrong way?