Hi, just recently, my i3 mk2s's x axis motor stopped working. I tried plugging the x axis motor into the y axis port, an it worked, and I I put the y axis motor into the x axis port and it didn't work. It is mini Rambo board

If you did not change anything in the Firmware, it sounds like you migth have burnt a stepper driver. Unless your soldering skills are superb, I fear this is the end for your mini RAMBO Board...