LoraMac. Adaptive data rate - how to swich on it?

Hi everyone!

I have stm32L072 chip and sx1272 lorachip.

I had developed a simple end-node device with stm32 lrwan library and endnode example for nucleo board.

Developed by Atollic True Studio.

Versions is: MAC_VERSION= 04.04.02.00 and STM32CubeExpansion_LRWAN_V1.3.1

options that i had used to:

1. LORAWAN_ADR_ON - true;
2. Global define REGION_EU868;
3. server's prefer DR is 5 (SF7);

Questions:

1. why uplink from device is always SF12? I think that the datarate should change itself or am I wrong?
2. how to make it "true" ADR?