Microcom modem loses internet connectivity

[Eltoro]

I've got a Microcom ADSL Deskporte 2622 modem.
Problem is it loses internet connectivity somehow. I would browse the internet for a few minutes and the next minute a page won't load. When I open network connections it still shows it's status as connected. Then after 5 minutes it would redial and connect again

Network connection detail
Device type :isdn
Server Type PP
Transports :TCP/IP
Authentication AP

PLEASE HELP !!!