Step 1: Go to Settings > Connections. Step 2: Tap on Mobile Networks. Step 3: Tap on Network Mode. Step 4: Select LTE/3G/2G (Auto), LTE/CDMA, or one of the other 4G/LTE options to prevent the phone from using 5G.
Read moreCan you use 4G on Samsung S21?
The Samsung Galaxy S21 Ultra has now been configured for use of 4G networks .
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