You change it by changing the channel you use. if you go into the wifi settings in the app, it will by default choose what it thinks is the best signal, since 2.4 is generally more powerful, it will usually default to that. However, if you choose "custom" and scroll down to "Channel Index" you can chose different channels, and depending on the one you chose, will choose 5.8 or 2.4. see screenshots
Notice it says 2.4Ghz
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Its becuase the channel is 2, which is a 2.4Ghz Channel
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if I change it to 165, which is a 5.8Ghz Channel
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It flips to 5.8Ghz
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