@Jbug92
The 3920 is a bit older device and is also a 2.4ghz-only device. (will not see or connect to 5ghz band of a network).
My 3921 is still running fine, so presuming that the age of device and some internal hardware/antenna failure is not the culprit, you will need to verify that the 2.4ghz band of your network is still enabled/on and verify that it is configured to use a Wireless Mode/Protocol of b/g/n. Then verify that it is only using a Wireless Channel between 1 and 11. Try lowering the Bandwidth/Channel Width to 20mhz. Finally, verify that under the Security settings (wifi password), you are using WPA2-Personal.
For the hotspot, also make sure that the 2.4ghz band is enabled or look for a setting similar to 'Maximize Compatibility" that will enable the 2.4ghz as well as the 5ghz bands for devices to connect to.
Are you getting a specific error message number in the message box?
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