Kindly follow the below settings:
realme UI 7.0 & 6.0: Settings > System & updates > Backup & reset > Reset phone > Reset Network & Bluetooth settings
realme UI 5.0 & 4.0: Settings > Additional Settings > Backup & reset > Reset phone > Reset Network settings
realme UI 3.0 & 2.0: Settings > Additional/System Settings > Backup & reset > Erase all Data > Reset Network settings only
realme UI R & Go & T & S Edition: Settings > System > Reset options > Reset Wi-Fi, mobile & Bluetooth
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