Laravel - 2个连接之间的差异

I have a Laravel project that communicates with a remote database and I have a problem that I can't understand.

For example, in my localhost, I have to set the connection to IP: PORT.
When I install in another PC, I have to put IP,PORT with a comma, otherwise it doesn't work.

Another difference is that a number in localhost as 10 and in another PC with 10.0000.

Why does this happen?