@v_gerzha I cannot tell you, I have no scara. In general X0Y0 is front left.
The coordinate system is explained in https://duet3d.dozuki.com/Wiki/ConfiguringRepRapFirmwareSCARAPrinter in section Scara description and in section calibration.
The three possible errors are from my experience with other rotating arms, in this case the parallel scara, where I had a similar result with wrong settings. You could change the 3 parameters and check whether the result gets better, but I would change only 1 parameter with every test, otherwise you don't know which one was the reason.
arm length: from hinge middle to hinge middle
angle: exact angle when the endstop triggers
gear ratio: recheck the datasheet if it's a stepper with gearbox
fourth: when Z actuator is fixed, the proximal and distal movements must stay horizontal while they rotate
also check: Xxxx and Yyyy X and Y offsets from the location of the proximal joint. (parameters, see documentation of link above)