I had similar issue today while doing playwright training course...my tests were running twice! It took me sometime before to realise I had 2 'chromium' settings under projects (probably bad copy-paste😅) double-check your 'playwright.config.ts' file to make sure you haven't line duplicated by error as below
projects: [
{
name: 'chromium',
use: { ...devices['Desktop Chrome'] },
},
{
name: 'chromium',
use: { ...devices['Desktop Chrome'] },
},
{
name: 'webkit',
use: { ...devices['Desktop Safari'] },
},