@slohcine Hello, welcome to the forum 
Steinberg’s Asio driver for UR44 is the most efficient to use.
If you have installed it correctly (and updated it), it should appear in a list by clicking in the device window of the MG2 audio interface panel.
In my case, for my UR22, Steinberg is displayed and I select it.
For standard, trouble-free use, in the MG2 Interface window, click on Driver and set the buffer size to 128 or 256.