Have there been any changes to your local network including Wi-Fi (New modem, changed network password, added devices)?
Try this: Go to network settings.
Find your local network and select, "Forget"
Then do a refresh on available networks. Once you see your local Wi-Fi network, re-enter the password for your network and see if it connects.
If not, then I'd probably recommend backing up your data to an external USB and then performing a hard reset on the device. This wipes out any changes or apps you've installed and resets the device to it's out of the box conditions/settings. Barring a hardware failure, this SHOULD restore your network connectivity. Then it's just a matter of reinstalling apps and restoring your saved data.
-Wolf sends
P.S. a quick Google of hard resets for your device gave me this:
https://www.google.com/search?client=firefox-b-1-d&q=RCA+Voyager+III+Hard+Reset
You might want to look into a few more options before settling on any one course of action.