Not Found Error While accessing 127.0.0.1:8888/phpmyadmin/ on Google Cloud

I was migrating my website from bluehost server to Google Cloud Platform using duplicator – wordpress Migration Plugin. On Google Cloud Platform I Installed WordPress Google Click to Deploy Virtual Machine. Right now I am having database error “Error establishing a database connection”.
to fix database connection error, I tried to access phpmyadmin using SSH tunnel but while I am trying to open https://127.0.0.1:8888/phpmyadmin/ I am encountering with 404 not found error. Can anyone help me fix the issue?

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