The solution below provides the connection line paths of the charging circuit.
To fix the problem, you may first ensure that the wall charger you are using is properly working and the battery is not totally drained. Continue by checking the charging pin connector or DC jack connector, visually check it for possible damaged. Clean the PCB board charging pads and battery connector. If the problem still occurs proceed to components troubleshooting.
First check the fuse if open or damaged, second check the diode if shorted. Check the 330hms resistor near the power IC. Re-solder or replace if damaged. Trace the VCHARGE (charging voltage) line paths and the ground of the charging pads.
If the procedures above doesn't solved the charging problem, the possible faulty is the power IC. Rework or replace if necessary.
Nokia X2-01 Not Charging Problem Solution