I generated my public-private keys on my computer
The public key I generated is as follows
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDTM3281UZhiful8xkk77roOxN1RNHkar+4nneTpJ3PKYUyD8/7sk5cZo7tWAkD6Z7Ot1rvvIDDHr74CSYuPjtzzn0RnGcKMp5ZaxngvuT1wfqPqkBsVV6czS4Gti/UZwWq5ZfmaTy8gFzCvfI5mWWPxF8BUwBmn9c7ek49CXS4tkQrd+UBqA2z9H2JQquCZGm0LeR8mdwbZZP4XsFETf/YttiwdraLli3Btt4767aNbnhY+LgnHWMVw4zWVSNE0v//BJ3qoqcOwmSy3O6For7I1S5/JlYKxMiYRhXxj359sPb60nE6e8Y5pX92U8sr1uv7vQxJrMA114ao5peU0LEZ user@MY-PC
My router uses OpenWrt 18.06. I then log into my router by SSH (still using password) and copy the above public key (beginning with AAAA.. and ending with ..LEZ) to /etc/dropbear/authorized_keys.
Also I am not logging in as root (I have created another user and disabled root access), I had read that I should also create the same file in ~/.ssh/authorized_keys so I did that as well.
All files are chmod 600 and their directories are chmod 700
However I still can't log in with putty, says "server refused our key". Have been struggling with this for so many hours.
Can someone help me troubleshoot this issue?