What caused ZTE to be sanctioned?

The United States does not allow domestic enterprises to sell things directly or indirectly to Iran (the United States is sanctioning Iran). ZTE secretly bought American things and sold them to Iran, which violated American laws and was caught by the US Department of Commerce. It was fined nearly $6,543.8 billion, and all American enterprises were required to stop selling parts to ZTE. But it was suspended. Later, the rectification measures proposed by ZTE were not in place, and the United States was pulled out of the Sino-US trade war by using the Sino-US trade war; To sum up, the ass is not clean, just bad luck, so bad luck.