Disgusted at the running of this hospital

All went well during admissions day and rhe person admitting said all was fine authorisation etc to then come to find out after doing g the test I came un for, by phone call from accounts department that I had to pay a co payment which I am not prepared to pay as the reason why I came in in the first place was not to pay. It is not my fault they are ***********. If I were told before.coming I would not have come at all. Do they think mo ey grows on trees