Arduino Nano doesn't upload after bad desolder

Hi, I needed to desolder my Arduino Nano from a badly designed "permanent project". After spending 2 hours of desoldering all pins from the protoboard, I think I damaged it. It worked for several uploads occasionally, but most of the times it gives something like "avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x00". The lights are on (obviously) and because I saw it perfectly working after the desolder, I guess it is software related (my pro mini and uno are just fine)

edit: The code is uploaded when I used Arduino uno as ISP, if it helps any

Do a very careful visual inspection of the board for any solder bridges or shorts caused by little blobs of solder or other conductive debris on the board.

poyrazyongaci:
edit: The code is uploaded when I used Arduino uno as ISP, if it helps any

Note that when you do that you erase the bootloader, which will cause you to no longer be able to upload normally via the USB connection. In order to go back to normal uploads, you will need to first do a Tools > Burn Bootloader.