Do you want to see my tax credit details, too?

During M's stay, the Housing Executive sent me a letter asking me to show them my tax credit details. Strange that I've shown them the same stuff some month ago. I wonder what's going on. Then, another letter came. The Education Board, too, wanted to see my tax credit details! Why am I suddenly so popular with the civil servants?? No worry, though. After going to the housing office (T was there again! but looking rather depressed this time), put my tax credit letter in an envelope and sent it to the board. Why can't the government offices share individuals' information? It would save loads of time and money, you know.