Tipically, the micro-USB of Arduino clones are poorly attached. They tend to break apart, as it happened to me. And if it does, the copper tracks get broken, too
This Arduino Pro Micro is a cheap clone, but instead of throwing it away, i will show a simple technique to fix it as an alternative to the trash dump.
Step 1: LOCATE WHERE THE USB TRACKS CONNECT
Using a magnifying glass is better than the naked-eye.
In this case, the Arduino have the USB connections respectively to the indicated resistors and diode (shown on the pictures). Once you made the diagram, move to the next step (SOLDERING).
IMPORTANT: Please refer to labels in the picture in STEP 2 for connecting the cables from the USB, i will update the diagram in this step some day...
Step 2: SOLDER THE USB CABLES
This is the worst part. Hope you have a good hand.
At first, use tin for the naked tip of the cable, and when soldering to the PCB, do NOT use excess tin.
NOTE: FOR THE GROUND CONNECTION OF THE USB CABLE, JUST PLUG IT ON ANY GROUND CONNECTION OF THE ARDUINO (GND).
Step 3: FINISH IT
Check on the Arduino IDE if everything is working right.
Add an epoxy or hot-glue finish to the solderings, because they are VERY FRAGILE.
Salute, and enjoy your zombie-Pro-Micro.