SQlite: Data is only get inserted first time in table and second time it does not

The data we are inserting in table the first time it get inserted while on second time(like second entry)it does not, What should be possible reasons if you can not read and understand my code then we can discuss the reasons

package com.example.sarahn.locationactivity;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.widget.Toast;


public class HelperAdaptor extends SQLiteOpenHelper{
public static final String DATABASE_NAME = "mmhdatabase";
public static final String TABLE_NAME3 = "timetable";
public static final int DATABASE_VERSION = 2;
public static final String NAME1 = "_timeprofilename";
public static final String TIME_PROFILE = "selecteddtimeprofile";
public static final String START_HOUR = "starthour";
public static final String END_HOUR = "endhour";
public static final String START_MINUTE = "startmin";
public static final String END_MINUTE = "endmin";
public static final String CREATE_TABLE3 = " CREATE TABLE " +TABLE_NAME3+  "   ("+NAME1+ " STRING PRIMARY KEY, " +START_HOUR+ " INTEGER, " +END_HOUR+ "     INTEGER," +START_MINUTE+ " INTEGER, " +END_MINUTE+ " INTEGER, "            +TIME_PROFILE+ " INTEGER); "  ;
public static final String DROP_TABLE1 = " DROP TABLE IF EXISTS "            +TABLE_NAME3;


public Context context;

public HelperAdaptor (Context context) {
    super(context,DATABASE_NAME, null, DATABASE_VERSION);
    this.context= context;

}


@Override
public void onCreate(SQLiteDatabase db) {


    try {

        db.execSQL(CREATE_TABLE3);

    }catch (SQLException e)
    {

    }

}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

    try {

        db.execSQL(DROP_TABLE1);


        onCreate(db);


    }catch (SQLException e)
    {

    }

}


public boolean insertdatatime(String nametime, int hrstart , int hrend ,     int minstart, int minend, int pr) {

    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues contentValues1 = new ContentValues();
    contentValues1.put(this.NAME1, nametime);
    contentValues1.put(this.START_HOUR, hrstart);
    contentValues1.put(this.END_HOUR, hrend);
    contentValues1.put(this.START_MINUTE, minstart);
    contentValues1.put(this.END_MINUTE, minend);
    contentValues1.put(this.TIME_PROFILE, pr);

    long id = db.insert(this.TABLE_NAME3, null, contentValues1);
    if(id == -1)
    {
        return false;
    }
    else {
        return true;
    }

}


}