I had the same trouble recently, but I just apologised to the Indian lady and told her I could not understand a word she was saying, and asked her if she could put someone else on, she promised she would and that they would phone me back, this they failed to do.
The next day I phoned again, this time I got a chap who presumably was English, he just could not do enough for me, one would think we had known each other for years.
One would think that when setting on call centre personnel, a simple test could be carried out to see if the person was easily understood, and knew what they were talking about?