Please ensure that both VCC_IO and +VM are being powered, with +VM connected to a voltage source >6V as this powers the internal blocks.
VCC_IO needs to be connected to a voltage equal to the logic level high of the microcontroller or adapter you are using. If VCC_IO is connected to 5V and your microcontroller outputs 3V for a logic high then the data would be under the threshold of the TMC2226 input logic value.