Slow internet connection

Have a Dell Inspiron 5567 laptop.  Most of the time it works fine and have good WiFi internet connect.  Then, connection speed slows dramatically until a significant Windows 10 update.  After installing the update speed returns to expected level.  This lasts for a while, then slows again until, you guessed it, another update.  Any ideas why this happens and how I can do a system reset to restore speed without waiting for the update?