Settings => App Management => Installed => « Wi-Fi » => Permissions => Allow All.

Settings => Dual SIM & Cellular => App Using Wi-Fi and Mobile Data => « Wi-Fi » => Service => Select ' Wi-Fi and Mobile Data'.

Settings => Battery => Energy Saver => « Wi-Fi » => Doze => Turn OFF.

Settings => Battery => Energy Saver => « Wi-Fi » => Abnormal Apps Optimization => Turn OFF.

Settings => Battery => Energy Saver => « Wi-Fi » => Background Freeze => Turn OFF.Settings => Battery => Low Battery Mode => Turn OFF.Security => Privacy Permissions => Startup Manager =>« Wi-Fi » => Turn ON.Security => Privacy Permissions => App Permissions Management => Activate all on ALLOW for « Wi-Fi ».Settings => Security => Homescreen Acceleration Ball => Turn OFF.Settings => Security => Self Diagnosis frequency => Turn OFF.Settings => Additional Settings > Application Management => Installed => « Wi-Fi » => Permissions => Allow All.Settings => Dual SIM & Cellular => App Using Wi-Fi and Mobile Data => « Wi-Fi » Service => Select ' Wi-Fi and Mobile Data'.Settings => Battery => Energy Saver => « Wi-Fi » => Automatically optimize when an abnormality is detected => Turn OFF.Settings => Battery => Energy Saver => « Wi-Fi » => Freeze when in background => Turn OFF.OPPO (Android Battery => Low Battery Mode => Turn OFF Data saving >Add apps that run in background> add “Wi-Fi” app.Power manager >Excess background battery usage > “Wi-Fi” ON.Privacy permission > app permission management >manage by app > select “Wi-Fi” > all permission.

Privacy Permission > Auto run management > “Wi-Fi” ON.

Open Security Center or Security Settings

Whatsapp installation procedure