App router mismatch

[Frontendxperts]

Hello, i am facing issue on prod vercel account. Local and dev vercel environment works alright no issue.

My app directory:
app/certify/page.jsx was the original route this was working correctly in both local and dev vercel setup.

BUT as soon as I deploy same code on prod vercel account
app/certify/page.jsx break it didn't find the route..

then I had to make
app/certifyy/page.jsx and it worked.

my package.json:

"dependencies": {
"@headlessui/react": "^1.7.17",
"@headlessui/tailwindcss": "^0.2.0",
"@heroicons/react": "^2.1.3",
"@tailwindcss/forms": "^0.5.3",
"@vercel/analytics": "^1.3.1",
"antd": "^5.13.3",
"autoprefixer": "^10.4.12",
"axios": "^1.6.8",
"clsx": "^2.1.0",
"localtunnel": "^2.0.2",
"lodash": "^4.17.21",
"next": "^14.0.4",
"next-translate": "^2.6.2",
"rc-steps": "^6.0.1",
"react": "^18.2.0",
"react-currency-input-field": "^3.8.0",
"react-dom": "^18.2.0",
"react-input-mask": "^2.0.4",
"react-phone-input-2": "^2.15.1",
"react-phone-number-input": "^3.4.1",
"tailwindcss": "^3.4.1"
},

both my prod and dev vercel build on same nextjs version.

Please guide whats the issue?