Open router settings,search for option like wireless 5.8g. open the setting and select the disable option and click save . Your 5.8g will get disabled.
Read moreHow do I turn off Samsung Galaxy S20 Note 5G?
How to turn off Galaxy Note 20 or Note 20 Ultra
Read moreHow do I turn off 5G on my Samsung Galaxy S20 Ultra?
To turn off 5g on Samsung S20, go to settings and scroll down until you find “network” then tap it. From there, select “more connection settings” then change the setting for “5G NR” so that it will read disabled or not present.
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