"No answer from phone line."

My sister has been trying to get through to the eye clinic but to no avail. This has been going on for the last two weeks. She was referred by the diabetic nurse who told my sister she would have to wait a couple of weeks for an appointment. It has now been nearly five weeks and not a word. The phone rings and rings and no one answers it.Her eyesight is deteriorating day by day and she is finding it very hard to see. Surely there must be someone there to answer the phone or are you so short staffed that this can't happen.