I Am Kco Severe Depression.anxiety Neurosis Since Last 20years .Initially

I am kco severe depression.anxiety neurosis since last 20years .Initially for 10 years I was started with sertraline(ssri) but gradually over period of time this drug was not making me comfortable and my psychiatris started venlafaxine(snri) and clonazepam.but now again I am facing problem of severe depression.and anxiety.kindly advice which medication shold I start now.