File not found on my online server

I also tried as advised to leave my file names in lower case (Home.php -> home.php) and by modifying my Routes.php file (Home::mytest -> home::mytest),

The change is wrong. You should not do like that.
You must name the file in the exact same case as the class name.
Because filenames in most servers are case sensitive.

E.g.,
1. if the classname is Home, then the file name must be Home.php
2. if the classname is home, then the file name must be home.php.

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