Resources under 'public' is not accessible from sub-domain

I have a Laravel 5.2 setup accessible from multiple sub-domains but using different database. i.e.

Domain : sample.com,      DB : sample-db
Domain : test.sample.com  DB : test-db

to change DB connection based on domain, I setup a middleware. Which is perfectly working.

Now, sample.com was previously setup and is working perfectly fine and able to access all resources under public directory. but test.sample.com is not able to access any resources from public directory.

via Chebli Mohamed