After failure ivf, I checked to see my ovulation but on da 12 after period I didn't do ovulation. Is it normal maybe due to stress. When ovulation occur?

Normal. After an ivf cycle it is common for the next month's ovulation to be delayed. All the medications that are given for the ivf cycle can take a few extra days to get out of your system before a new ovulation will start up. Ivf is also very stressful so that can play a part as well. I have had patients who conceived on their own the month after a failed ivf cycle. It can happen.
Ovulate after IVF. Most women resume normal cycles and menses after ivf. Ivf is physically and emotionally stressful which could prevent ovulation as well as left over hormones. Some women do not ovulate on d12 and that is another possibility. Overall, I think you should relax because you will almost certainly resume your normal pattern of cycles next month if this cycle is off. Best wishes.