"Blood sample data not stored"

I had blood samples taken recently ready for a blood transfusion later in the week.

In the afternoon after attending, I had two phone calls telling me the samples ( not just mine, all match and save samples) have not had the data stored. I would have to go back the next day for more blood to be taken.

I am a wheelchair user and it is 5 miles each way to get this draw done. Usually I have to book transport a week in advance but have managed to get a non-WAV where the driver has said there will be assistance in and out of the car and the chair will go into the boot. 

I want to know how this can happen - blood test results in effect being lost - and how serious this is. Luckily I have a day in hand but presumably some people will have had their transfusions cancelled. Is there no backup protocol? How worried should I be that this will happen again?