android sqlite query with offset doesn't return desired rows

I'm using the following code to get a list of notifications (total rows are 21):

List<Notification> list = new ArrayList<Notification>();
Cursor c = _db.query(TABLE_NAME, COL_ALL, null, null, null, null, order, get_limitStr(offset));
if(c != null && c.moveToFirst())
{
    while(!c.isAfterLast())
    {
        Notification model = cursorToModel(c);
        if(model != null)
        {
            list.add(model);
        }
        c.moveToNext();
    }
    c.close();
}

and the generated query for offset = 0 is

SELECT Id, Token, Title, Read, Message, Image, CreateDate, CreateDateFA FROM Notifications ORDER BY CreateDate DESC LIMIT 20,0

and it works as it's supposed to and returns 20 rows, when I increase offset by 1 (offset = 1) it returns only 1 row which is correct but the problem is when the offset is bigger than 1 then the query will be

SELECT Id, Token, Title, Read, Message, Image, CreateDate, CreateDateFA FROM Notifications ORDER BY CreateDate DESC LIMIT 20,2

and I thought it supposed to skip 20 * 2 rows and then starts taking rows from there, which either my thought or my query is wrong. What am I doing wrong here? Thanks