I have completed all the challenges but the last one is giving me problems. Here is the linkhttps://trailhead.salesforce.com/content/learn/projects/develop-app-with-salesforce-cli-and-source-control/merge-feature-branches-and-deploy-metadata

@Divaker Singh (Girikon LLC) , yes I was able to deploy push changes successfully. I had to create another playground and followed the process again, ensuring that all cloned files from sfdx-chan exist on sfdx-maria. I had to do this because the initial clone didn't include everything even after I manually copied from Chan to Maria, it still didn't work.  Thanks for your response. @Srinivas Prudhvi Kota