Diagnosis
The printer's network connection is fine, but the spooler service on your computer (or the printer's sleep state) has lost the handshake. Windows is particularly bad about this.
How to Fix It
First, on the printer itself, press the WiFi button to ensure the blue light is steady. Then, on your Windows PC, go to Settings > Devices > Printers & scanners. Click on your Canon G7020, select 'Open queue'. In the new window, click 'Printer' in the menu bar and make sure 'Use Printer Offline' is NOT checked. If it is, uncheck it.
If That Didn't Work
Delete the printer from your computer entirely. Then re-add it by selecting 'Add a printer' and letting Windows search for it. Often, the fresh driver install clears the stuck status. Use the Canon PRINT Inkjet/SELPHY app for a more reliable connection from phones.
Heads Up
The printer's eco-mode or deep sleep can cause this. You can adjust the sleep timer in the printer's device settings, but leaving it on all the time will use more power.