The new smart plug says “2.4 GHz only”, while your phone shows a 5 GHz connection. It is tempting to rebuild the home network before opening the box. First check whether there is actually a compatibility problem or just a requirement during setup.
One name can cover several bands
Google’s Nest Wi-Fi documentation explains that its bands operate together under one network name. A supported device can use 2.4 GHz while another uses 5 GHz. The phone’s current band alone therefore does not tell you whether a 2.4 GHz device can join.
Write down the exact smart-device model and look at its instructions. “Uses 2.4 GHz” describes the device; “connect your phone to 2.4 GHz during setup” adds a separate requirement. For example, TP-Link’s Kasa setup guide asks for a phone on 2.4 GHz and, on recent iOS versions, Local Network access for the app.
Find the step that fails
Before changing the router, note where the process stops:
- Does the app discover the device in setup mode?
- Does the device accept the chosen home-network name and password?
- Does it join, but remain unavailable in the app?
These observations make a support request much more useful than “Wi-Fi does not work”. Repeat one step at a time and keep a short note of what changed.
Use the router’s documented option
If the device requires a 2.4 GHz setup connection, check your router’s own instructions. Some models provide a dedicated IoT network with a selectable band; TP-Link documents this on supported routers. Do not assume your model has the same controls.
Avoid changing the main network name, password and security mode together just to test a guess. If the manual requests a temporary setup change, record the original value, complete the pairing and restore it as directed. Then test the device from the place where it will actually be used.