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Not so many but I have several time that the prototype made from TI ref design. It's not running (or burned, or nothing in secondary side) at first time. Some reason is Transformer, feedback, layout... So, I took time to read book and datasheet (DS) carefully.

First, the DS show that your VDD need in range: enter image description here

Second, R7, you need ~200k Ohm (according calculation), and you should use 2x 100kOhm (not 1 resistor 200k)

Third, be careful with transformer pol. If , for example bias winding is wrong, simply rotate the dioe 180*C