Bad day

What can be worse, but to receive an email after the weekend, from a client telling you that you have made a mistake. No, the mistake is minor. If he sums it up, he would have gotten the right figure. But that's not the point. Point is SKH has made a mistake and the client's big boss is angry, so he is withholding payment and now SKH's boss is angry because the company will not get paid. Like he said, it's one cell which is wrong in the thousands of cells. But too bad, I had to be so careless with the department that mattered the most. Darn. Stupid.