Unhappy [Q] Wifi Problem

When i Bought the phone the wifi seems to work properly and the use computer internet connection was working properly.
There was a rom update available in updater In tools folder.
I installed the update.
After that my wifi cnnection is not working properly.
It gets disconnected automatically after 1-2 mins and reconnects automatically but takes time.
I have tried different wifi connections available this problem comes with all the connection.
After installing the update the use computer internet icon is also not shown in the notification tab.

What should i do to solve wifi problem?