"Failure to receive compression stockings that were prescibed"

In January 2018 I had an ablation operation at High Wycombe hospital, this was to ease a DVT and help prevent further painful ulcers. Mr Northeast said that I needed to wear compression stockings for life. I was told that it was my responsibility to ask for the stockings after 6 months. To do this I needed to phone Amersham hospital and request them, they would order them, and upon their delivery send them to High Wycombe Physio dept for me to collect. This worked well for the first 18 months but I asked for more stockings in September, when I had received no notification of them after a month (the usual time it takes for delivery) I phoned to see if they had arrived. The phone always goes to answer phone asking for name etc and that your call will be returned, this has not happened, despite numerous calls. It is now 2 months since I asked for the stockings, and I am getting extremely anxious as  my current stockings are beginning to lose their compression. I am aware how busy  the dept must be but surely somebody can get back to me, and inform me when I will receive the stockings.