Epson Tm-30 epos Printing using javascript Issue with connection timeout in web app

Question

We are using epos JavaScript 2.9.0 to connect and print receipts via our webapp from Android devices. But we are getting only connection_timeout error all the time. Sometimes though it works and is very unstable. It works fine from the connected pc .

Here is my code:

var ePosDev = new epson.ePOSDevice();
ePosDev.connect('IP address', 'PORT', callback_connect);

callback_connect's resultConnect variable always return CONNECTION_TIMEOUT