Repotting causes more problems than many people realize. It is easy to do it incorrectly and inadvertently damage the tiny roothairs. In addition, adding more soil can alter the watering routing significantly. It is very common for problems to emerge several months after the repotting because it takes a while for the root damage to show symptoms. I suggest pruning back severely, keeping it warm and allowing the soil to dry out more than usual, providing just enough to avoid wilt.
