I’ve tried twice with no luck. This is my third purchase and it was going great for a couple of months. I water it once a week But now some leaves have dried up and falling off. What am I doing wrong :(
Unfortunately, your photos did not come through. It is hard to say what happened. You don't mention the size of the container, if it has drainage holes, and the conditions that you kept your succulent in. In the meantime, this article will offer information on the proper care of these plants:
https://www.gardeningknowhow.com/ornamental/cacti-succulents/burros-tail/burros-tail-care.htm
I have my plant indoors and I'm pretty sure it gets enough light. It's not shriveled and it shows no signs of it dying. So I don't know whats going on.
Unfortunately, your photos did not come through. I am unable to see the plant to get an idea of what is going on.
Usually, it will boil down to 3 factors- Soil nutrient content, temperature, and light amount.
These plants require warm temperatures and quite a bit of feeding during the growing season. They will require full sun, as well. This will mean that using a window to light them will give very slow results.
For a refresher on the plants' care, read this article:
https://www.gardeningknowhow.com/ornamental/cacti-succulents/burros-tail/burros-tail-care.htm
The burros tail is mostly very healthy and hanging outside with a bit of shelter from the sunlight. The top right side is suddenly shrivelling up and drying out. The rest of the plant seems healthy.
This specimen will appreciate being exposed, more and more, to full sun until it is in full sun all of the time! It will appreciate a slight dry out, but nothing like a true cactus would require. In fact, they will prefer to be on the moist side.
I would treat with a fungicide and start acclimating it to full sun. Here are some articles that will help:
https://www.gardeningknowhow.com/ornamental/cacti-succulents/burros-tail/burros-tail-care.htm
https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm