Typically, this would be a result of having less mowing time than needed. Check and add mowing days, increase mowing time window, increase mowing hours percentage if needed and even select Intensive mowing which will mow on Intensive mode for a week. If after doing all of these correction items grass still looks uneven, check whether Is the grass very high and is the RK height of cut set lower than its top 100mm (4 inch)? If this is the case, raise height of cut to the highest and let the RK mow for a week or so to see improvements. If the grass is much higher than the 100mm (4 inch) height, mow it manually with another mower or a lawn service to lower it to manageable height - 75mm (3 inches) or lower.
Wait a week and see whether the uncut patches are gone.
If issue remains: Contact Customer Support.