I have had four attempts to get my glasses made correct, first attempt the prisms were the incorrect way directing my vision to be double, the second time was right eye had a focus distance of only ten feet my left eye was correct, after have a further eye test, it was found that my eye sight had changed, it was suggested that my diabetes may cause this, I have not had diabetes for over one year, The latest was to wear the glasses for a further two week to get used to them,all I have had is a balance problem and continued me grain. I have just had an eye scan which involved having a photo of the back of my eye, this has shown clear, no sign of diabetes. I would like a full refund so I can go and have further free test with a different optician.