error: src refspec main does not match any. error: failed to push some refs to 'https://github.com/ruoshiliu/hypercuriosity.git' code example

Example 1: error: src refspec main does not match any error: failed to push some refs to

Check master vs main

Example 2: error: src refspec main does not match any error: failed to push some refs to 'https://github.com/majeduli/paul-template.git'

error: src refspec master does not match any.  
error: failed to push some refs to 'ssh://xxxxx.com/project.git'