New
#41
In this post, I suggested that you make a text file named ping router.bat
In this post, you posted a screenshot showing a ping to 192.168.1.110. The IP in the text file named ping router.bat should be changed to 192.168.1. 254. That will let you ping the router. The other batch file pings Google.
Anyway, I downloaded the manual for the NVG510 modem/router (such that it is). See if you can download the same manual so that we are on the same page - literally.
Follow the steps on page 19 to connect to the router/modem. If you do not know the password, contact the ISP support staff and have them help you to get in. You might have to reset the router/modem. They will know what (if any) settings need to be re-applied.
Once you are into the router/modem's interface, select the tab/link named Home Network, then click on the link named Wireless. You should be able to change the channel to channel 3 from that page.
Then keep an eye on things with those two batch files mentioned in the earlier posts to see if you are losing your connection to the router/modem or losing your connection to the internet. However, reading the link in post 40, I'm going to guess that the problem is with the router/modem.