DIAGNOSIS The brewer's 2.4GHz WiFi radio has a weak connection or conflicts with certain router settings, a common issue with this model.
FIX Move the brewer closer to your router, ideally within 15 feet with minimal obstructions. In your router's admin settings, ensure your 2.4GHz network band is active and not on a crowded channel (try channels 1, 6, or 11). During setup in the Keurig app, manually enter your 2.4GHz network name and password—do not use the 'quick connect' feature.
IF THAT DIDN'T WORK The brewer's network memory may be corrupt. Perform a network reset on the brewer: go to Settings > Network > Forget Network. Then reboot your router. Once the router is back, set up the brewer as a brand new device in the app.
HEADS UP This brewer cannot connect to 5GHz networks or networks that use WPA3 Enterprise security. If your router combines bands under one name (band steering), temporarily disable that and connect the brewer to the dedicated 2.4GHz SSID.