I am using D-Link modem DSL-2750U model. Recently I faced some issue with wi-fi connectivity. When I am using wi-fi after sometime the led light on modem will go off as well as sometimes my Internet light also goes off. Ultimately I am not able to use the internet. To fix the problem I always used to restart the modem after few minutes and it get starts but the same problem persist. I am not sure what's going on. Please advise if I need to replace the device. This is 8 months old so I still have 4 more months to use the warranty.
If its still in warranty, I would just get a new one.
Do you have more than one device that connects to it? Are they all having the same problems? If not, then it might be something wrong with your computer, perhaps a firewall or network configuration issue.
Getting simpler, if the modem itself isn't getting internet, that might be a wiring issue. These can be tricky, but you can sometimes call the internet company and they'll be able to check if the signals are right going to your port.