Is my octagonal gold basin sick? Look at the tips of his leaves, they are all black

There are some symptoms of calcium deficiency and the air humidity is insufficient when new leaves grow. I think your soil should be very compacted and not loose enough. The new roots are not growing, so the trace element selenium cannot be tolerated or the new roots are flooded for a long time. Soaked

The symptoms of lack of cover are poor growth at the growing point, deformation of leaf tips, whitening and dryness. You may not necessarily have calcium deficiency, but there must be something wrong with your soil. You can re-cut the cuttings, but it is not recommended because the weather is too cold now. Loosen the soil, water it until it becomes dry and then it will get better.